Download Biannual Report 2004/2005 - Software Science Laboratory

EC and Estonian
Centre of Excellence
Biannual Report
2004/2005
Tartu 2006
Prepared by H. Jõgi, M. Kirm and H. Käämbre
Front cover: Blue fluorescent protein
Courtesy K. Mauring
Back Cover: ZrO2 micro-tube self-assambled from a nanostructural
film V. Reedo, M. Järvekülg
Courtesy Estonian Nanotechnology Competence Center
Copyright Tartu Ülikooli Füüsika Instituut, 2006
ISSN 1406–7927
Tartu Ülikooli Kirjastus
www.tyk.ee
Tellimus nr 397
CONTENTS
Füüsika Instituut aastail 2004/2005 ............................................. 5
Institute of Physics in the years of 2004/2005 .............................. 10
1. Organization and Personnel ....................................................
1.1. Structure..........................................................................
1.2. Supervisory Board ...........................................................
1.3. International Advisory Board of the Institute ..................
1.4. Directorate......................................................................
1.5. Directorial Board ............................................................
1.6. Personnel ........................................................................
17
17
18
19
19
20
20
Estonian Nanotechnology Competence Centre............................ 26
2. Grants/Contracts and Cooperation Partners ........................... 29
3. Research Highlights ................................................................
Difference fluorescence line narrowing – an effective
selective spectroscopy tool for studies of complex
molecular systems ..............................................................
Probing anomalous ZZȖ and ZȖȖ couplings in e+e– ĺ ZȖ
with polarized initial beams ...............................................
Cuprate superconductivity caharcteristics on the doping
scale. A simple model.........................................................
How small a packet of photons can be made? .........................
Multiphoton processes in intense laser fields...........................
35
35
41
47
56
60
4 • Biannual Report 2004/2005
Decay of Anion and Cation Excitons into Frenkel Pairs and
Defect Triplets in LiF Single Crystals ..................................... 62
Resonant inelastic scattering at the F 1s photoabsorption
edge in LiF ........................................................................ 67
4. Scientific Report ..................................................................... 72
5. Publications ............................................................................ 128
6. Talks and Posters at Conferences ............................................. 157
7. Dissertations Prepared at the Institute..................................... 180
8. Graduation Theses Prepared at the Institute ........................... 182
9. Scientific Meetings Organized ................................................ 184
10.Visits to Research Centres Abroad .......................................... 186
11. Visitors .................................................................................. 195
12. Pedagogical Activities.............................................................
12.1. Lecture courses at the University of Tartu.....................
12.2. Supervising of PhD theses (postgraduates, doctoral
level) of the University of Tartu....................................
12.3. Supervising of MSc theses (postgraduates, master level)
of the University of Tartu.............................................
198
198
200
201
13. Awards .................................................................................. 203
14. Acknowledgements................................................................ 205
FÜÜSIKA INSTITUUT
AASTAIL 2004/2005
1947. a. asutatud ja sügisest 1997 Tartu Ülikooli koosseisus oma tööd
jätkav Füüsika Instituut on peamine füüsika ja selle sidusalade uurimiskeskus Eestis. 2005. a. lõpus töötas instituudis täiskohaga teaduri,
vanemteaduri või laborijuhatajana ligi seitsekümmend teaduskraadiga
koosseisulist teadustöötajat. Neile lisandub poolsada teadustööd
teenindavat töötajat: raamatukogu, peenmehaanika töökoja, heeliumit veeldava külmajaama ning majandusosakonna personal. Veel on
meie tegevusse lülitunud paarkümmend tähtajaliste lepingute ja
grandiprojektide täitjat.
Käesolev raamat jätkab Tartu Ülikooli Füüsika Instituudi trükis
avaldatud aruannete traditsiooni. Ta järgib ka eelmise 2002/2003
aruande vormi ja kujundust. Esimeses osas tuuakse andmeid instituudi struktuuri, juhtorganite ning personali kohta, samuti esitatakse
saadud uurimistoetuste ja lepingutööde nimistud. Järgnev osa
“Research Highlights” pakub lugejaile loodetavasti enim huvi, kuna
siia on koondatud lühiartiklid uurimisteemade valdkondade esileküündivamate tulemuste kohta. 4. osa “Scientific Report”, aruande
põhiosa, annab ülevaate instituudi uuringute olulisimatest tulemustest
sihtfinantseeritavate teemade lõikes. Järgnev on juba pigem formaalstatistiline kokkuvõte: publikatsioonide, konverentsiettekannete ning
kaitstud väitekirjade nimistud, kokkuvõte instituudi poolt korraldatud teadus-kokkutulekuist, andmed instituudi töötajate välislähetustest ning meie maja külastanud välisteadlastest, ülevaade instituudi
teadurite panusest TÜ õppetöösse jmt.
6 • Biannual Report 2004/2005
2004. a. aprillini jätkas instituut tööd Euroopa Komisjoni tippkeskusena ja kuni 2007. a.-ni jätkab ka Eesti tippkeskusena. Aastad 2004
ja 2005 olid instituudile väga edukad. Eesti Vabariigi preemia
pikaajalise teadustöö eest anti 2004. aastal meie teenekale kolleegile
akadeemik Tšeslav Luštšikule, preemia viimaste aastate teadussaavutuste eest said täppisteaduste alal prof. Nikolai Kristoffel (2004) ja
tehnikateaduste alal (2005) kollektiiv, kuhu kuulusid ka Rünno ja
Ants Lõhmus. 2004. a. lõpus õnnestus edukalt käivitada Ettevõtluse
Arendamise Sihtasutuse (EAS) poolt rahastatav NanoTAK. Aruanne
selle tegevusest esimese aasta jooksul on lisatud ka käesolevasse kogumikku. 1. juunil 2005 alustas tegevust materjaliteaduse ja materjalide
tehnoloogia doktorikool, kus partneriteks on Füüsika Instituut,
füüsika-keemiateaduskond, TTÜ ja KBFI. Enamuse meie maja
doktorantide rahastamine toimubki läbi eelpoolnimetatud doktorikooli. FI oli edukas ka teaduse tippkeskuste infrastruktuuri rahastamise taotlusvoorus, mida kureeris samuti EAS – rahvusvahelise
komisjoni hinnangul osutus FI projekt kümne taotluse esitanud tippkeskuse seas parimaks. Sellega kaasnes 17,8 mln kroonine toetus
aparatuuri kaasajastamiseks ja infrastruktuuri renoveerimiseks, millest
suurem osa leiab kasutamist 2006. a. Kahjuks ei käinud meie käsi nii
hästi teaduse infrastruktuuri programmist rahade ühistaotlemisel
osana konsortsiumist koos ülikooli mitmete teiste struktuuriüksustega. Meie taotlus ületas küll vajaliku hinnangukünnise, kuid
rahajagajal olid vahendid selleks ajaks juba otsa lõppenud …(!)
Edukas koostöö on instituudil olnud mitmete suurte ja väikeste
firmadega. 2005. a. juunikuus kirjutasime alla lepingu elektroonikahiiglasega “Samsung” plasmateleviisorite paneelide materjalide uurimiseks. Koostöö sujub hästi ja loodetavasti saab edukatest tulemustest
kirjutada järgmises kogumikus. Samuti teeb instituut uuringuid ka
Eesti firmadele ja sihtasutustele – alla on kirjutatud lepingud Keskkonnainvesteeringute Keskusega ja Tallinna Sadamaga naftareostuse
detekteerimismeetodite väljaarendamiseks. Eesti väikefirmadega on
tihe koostöö NanoTAK-i raames, samuti jätkub konstruktiivne
Füüsika Instituut • 7
koostöö Tartu Teaduspargiga. 2005. a. sügisel tähistasime peahoone
valmimise kolmekümnendat aastapäeva, avasime pidulikult uue
multimeedia õppeklassi ja kaasaegselt sisustatud pinnafüüsika laboratooriumi, millele aparatuuri hankimiseks andis juba 2001. a. esimese
“seemne” Rootsis tegutsev Erna ja Victor Hasselbladi fond.
Aasta 2005 kuulutati UNESCO poolt füüsika aastaks, selle raames
võttis instituut endale ülesandeks tegelda füüsika ja üldse teadusliku
maailmavaate populariseerimisega. Ajakirja “Horisont” 2005. a. igas
numbris ilmus üks või mitu artiklit instituudi töötajate sulest, milles
autorid tutvustasid oma teadustegevust ja antud teadusala probleeme
laiemalt. Selline “dessant” äratas ka laiemat huvi ja FI pälvis 2006.a.
alguses selle artikliseeria eest MTÜ Loodusajakirja aastapreemia “Seest
suurem Eesti”. Füüsika populariseerimisel olid väga tublid ka meie
nooremad kolleegid, doktorandid ja magistrandid, käivitades Eesti
Televisioonis hommikused “Terevisiooni” füüsikakatsete minutid.
Samuti osalesid nad väga aktiivselt “füüsikabussi” käivitamisel ja selle
aastaringsel käigushoidmisel. Selle tegevuste eest pälvisid nad
Haridus- ja Teadusministeeriumi teaduse populariseerimise esimese
preemia.
Ajast aega on meie ja Tartu Ülikooli füüsikaosakonna tegevus
olnud tihedalt põimunud. Enamik ülikooli füüsikaprofessoreid on
tulnud instituudist ja jätkavad oma uurimistööd meie laborites.
2005. a. lõpu seisuga töötas instituudis siinsete teadlaste juhendamisel
üle kuuekümne üliõpilase, magistrandi ja doktorandi. Instituut on
ikka püüdnud aiva agaramalt osaleda ka auditoorses õppetöös. Et
veelgi tõhustada meie teadlaste panust selles tegevuses, loodi Tartu
Ülikooli füüsikaga tegelevate institutsioonide katusorganisatsioon
Füüsikum. Õppetöö parema koordineerimise huvides avasime instituudis õppedirektori ametikoha. Detsembris 2005 moodustati teadusnõukogu otsusega laboreid ühendav materjaliteaduse osakond, et
senisest veelgi edukamalt teadus- ja arendustöid läbi viia.
Teaduse riigieelarveline rahastamine toimub Eestis peamiselt
sihtfinantseeritavate teemade kaudu. Need hõlmavad suhteliselt laiu
8 • Biannual Report 2004/2005
valdkondi ja määratakse kindlaks kuni viieks aastaks. Sedakaudu sai
instituut 2004. aastal 13,2 mln krooni ja 2005. aastal 14,4 mln
krooni sihtsuunitlusega raha. Praegune rahastamisperiood algas
2002. a. ja lõpeb käesoleva aastaga. Ees seisab tõsine ülesanne
pakkuda välja uued atraktiivsed sihtsuunitlusega teadusteemad järgnevaks perioodiks. 2004/2005 olid meie sihtfinantseeritavad teemad
järgmised:
1. Valgustundlike materjalide laserspektroskoopia ja nende rakendused (teema uurimisjuht prof. J. Kikas)
2. Nanostruktuursed materjalid (dr. K. Haller, dr. A. Rosental
alates 2005)
3. Biofüüsikalised elementaarprotsessid ja nende dünaamika
(prof. A. Freiberg)
4. Eesti keskkonna radioaktiivsus ja kiirgusdoos (dr. E. Realo)
5. Aine süvastruktuuri teooria (prof. V. Hižnjakov)
6. Laserifüüsika ja laseroptilised tehnoloogiad (prof. P. Saari)
7. Fundamentaalnähtused laia keelutsooniga materjalides ja
nende rakendusperspektiivid (prof. A. Luštšik).
Nende teemade järgi on liigendatud ka käesolev aruanne.
Aastal 2004 (2005) on Instituut saanud kasutada veel järgnevaid
summasid (mln kroonides): infrastruktuuri rahastamine 4,8 (5,1);
Eesti Teadusfondi grandid kogusummas 5,3 (6,7); Eesti tippkeskuse
finantseerimine 3,4 (3,0) ja mitmed tööstus- ja mittetulundusühingute lepingud. Instituudi teaduse finantseerimise reale lisandus
2005. a. baasfinantseerimine 4,0 mln krooni, mida direktor saab
kasutada uute uurimissuundade avamiseks ja teemade toetamiseks,
infrastruktuuri arendamiseks või välis- ja siselepingute kaasfinantseerimiseks. Teadus- ja arendusasutuse baasfinantseerimise mahu algoritmi
üheks olulisemaks teguriks on ISI andmebaasis kajastuvate asutuse
töötajate teadusartiklite arv. Et instituudi teadlaste osalusega artiklite
arv on viimastel aastatel näidanud mõningast langustrendi, otsusta-
Füüsika Instituut • 9
sime stimuleerida oma parimaid publitseerijaid nn publitseerimispreemiatega. Esimesed kokkuvõtted tegime 2005. a. publitseerimistulemuste alusel, kavas on seda jätkata ka edaspidi.
Füüsika Instituudis kasutada olnud summaarne rahamass oli
2004. a. 36,7 mln kr ja 2005. a. 40,3 mln kr. Kuid see ei hõlma veel
kõiki kasutatud summasid. Kõikidest meie uurimistööde rahastamistest polegi võimalik täpset ülevaadet saada, sest mõnede projektide
reisitoetused, toetused uurimistöödeks väljaspool Eestit jmt on sageli
kaetud väismaiste uurimiseralduste arvelt. Kahe siin käsitletava aasta
uurimistulemused on avaldatud kokku 246 publikatsioonis, kaasa
arvatud 140 artiklit eelretsenseeritavates ajakirjades. Meie teadurid
osalesid 116 teadusnõupidamisel, neist 89 olid rahvusvahelised.
Kokku esitati 235 ettekannet (112 suulist ja 123 posterit).
Mõningaid lisafakte Füüsika Instituudist ja kontaktandmed on
leitavad internetisaidist http://www.fi.tartu.ee/ ning mõistagi ka
instituudiga otse ühendust võttes. Kõik on selleks teretulnud!
Ergo Nõmmiste,
direktor
INSTITUTE OF PHYSICS
IN THE YEARS OF 2004/2005
The Institute of Physics (IPh), founded in 1947 and since the
autumn of 1997 functioning as a R&D institution of the University
of Tartu, is the main research centre of physics and associated fields
in Estonia. By the end of 2005, about seventy permanent research
workers with scientific-degrees were employed at the Institute as fulltime research fellows, senior research fellows or heads of laboratories.
In addition, there are about half a hundred research-work-assisting
employees, such as library workers, precision-mechanics technicians,
cryogenic plant specialists and economics department personnel.
There are also some twenty persons involved in our activities on the
basis of temporary contracts and grant projects.
This booklet continues the tradition of the scientific reports of the
Institute of Physics of the University of Tartu published so far. It also
follows the style and format of Biannual Report 2002/2003. The first
section contains data about the structure of the Institute, its
management bodies and personnel as well as the lists of the bestowed
science grants and contract works. The following section “Research
Highlights” is supposedly the most interesting one for the readers, as
here are concentrated short papers about the most remarkable results
of the research areas. Section 4, “Scientific Report”, the basic part of
the report, presents a survey about the most essential results within
the research topics supported by targeted financing. What follows is
more or less a formal-statistical summary: lists of publications,
conference reports and the defended theses, a summary of the
scientific conventions organised by the Institute, data about the
Institute of Physics • 11
assignments of the Institute’s researchers abroad, and about the
foreign scientists who have visited the Institute, a survey about the
contribution of our research fellows to the Tartu University study
courses, etc.
Until April 2004, the Institute continued its work as the
European Commission-designated Centre of Excellence and up to
2007 it will continue as the Centre of Excellence of Estonia. The
years of 2004 and 2005 were very successful for the Institute. In
2004, a state reward of the Republic of Estonia was bestowed to our
deserving colleague Academician Cheslav Lushchik for a long-time
research work, rewards for the recent years research achievements
were also granted to Professor Nikolai Kristoffel (2004) in exact
sciences and to a technical sciences group including Rünno and Ants
Lõhmus (2005).
In the end of 2004 we managed with a successful activation of
NanoTAK, financed by Enterprise Estonia (national support system
for entrepreneurship in Estonia). A report about its activities during
the first year has also been included into the present collection.
On June 1st 2005, the Doctoral School of Material Science and
Material Technology started its activities, where the partners are the
Institute of Physics and the Faculty of Physics and Chemistry
(University of Tartu), Tallinn University of Technology and National
Institute of Chemical Physics and Biophysics (NICPB). The
financing of most of our doctoral candidates takes place via the
aforementioned Doctoral School.
The Institute of Physics was also successful in the call for proposal
to finance the infrastructures of the Centres of Excellence, that was
also governed by Enterprise Estonia – according to the evaluation of
an international committee the project by IPh appeared to be the best
among ten excellence centres contender projects. The support money
totalled 17.8 MEEK, which is meant for modernising the equipment
and for renovation the infrastructure, most of which will be used in
2006.
12 • Biannual Report 2004/2005
Regrettably, we were not so lucky with our joint application of
financial support for the science infrastructure programme, which we
submitted together with a number of other structure units of the
University of Tartu as a part of the consortium. Although our application exceeded the required evaluation level, by that time the
provider’s money had just run out ... (!)
The Institute of Physics has had a successful co-operation with a
number of large and small companies. In 2005, we signed a contract
with the electronics giant “Samsung” on the investigation of materials
for plasma TV panels. This co-operation proceeds well and hopefully
its successful results can be reported in our next collection. The
institute also makes investigations for the Estonian companies and
foundations – contracts have been signed with the Centre of
Environmental Investments and Tallinn Port for developing the
methods of detecting oil pollutions. Within the NanoTAK IPh has a
close co-operation with the Estonian small companies, a constructive
co-operation is going on also with Tartu Science Park. In the autumn
of 2005, we celebrated the 30th anniversary of the opening of our
main building, inaugurated a new multi-media study class and a
modern surface physics laboratory, for which the first “seed” for
procuring the equipment was given by Erna and Victor Hasselblad
Foundation in Sweden already in 2001.
The year 2005 was declared by UNESCO the year of physics.
Within these frames the Institute of Physics made a commitment of
popularising physics and the scientific outlook on life in general. In
2005, in each edition of the magazine “Horisont” there appeared one
or several articles by the research fellows of IPh, in which the authors
introduced their scientific activities and the relevant scientific field
problems in general. Such “landing” generated also a wider interest
and in the beginning of 2006 IPh was awarded for this articles series
an annual prize of the non-profit Nature Magazine (MTÜ
Loodusajakiri) “Estonia – bigger inside” (“Seest suurem Eesti”). In
popularising of physics also our younger colleagues, doctoral
Institute of Physics • 13
candidates and master’s candidates were very enthusiastic, activating
in the Estonian morning TV (“Terevisioon”) programme the minutes
of physics demonstration experiments. They were also very active in
introducing „the physics bus“ and took care for its year-round
running. For these activities the Ministry of Education and Research
rewarded them with the first prize for popularisation of science.
From times on our activities have tightly been interweaved with
those of the Department of Physics of the University of Tartu. Most
of the physics professors of the university have come from the
Institute and they are continuing their research activities in our
laboratories. As of the end of 2005, more than 60 students, master’s
candidates and doctoral candidates worked in our institute under the
supervising of our scientists. The Institute has always tried to be ever
more actively involved in the auditory study work. To make our
scientists contribution in these activities more efficient Füüsikum, a
shelter organisation of the institutions dealing with physics, was
founded. To ensure a better co-ordination of the study work we
introduced a study dirctor post in the institute. In december 2005,
the material science department was founded by the decision of
Scientific Council, the aim of which is to carry out more succesfully
research and development activitities bringing different laboratories
together.
The budgetary financing of research takes mainly place via the
target-financed topics. These topics cover relatively broad fields and
these are fixed for up to five years. By this way the Institute received a
targeted financing in the amount of 13.2 MEEK in 2004 and
14.4 MEEK in 2005.
The present financing period started in 2002 and it will end with
this year. IPh confronts a serious task of proposing new attractive
target-financed research topics for the next period.
14 • Biannual Report 2004/2005
In 2004/2005, our target-financed topics were as follows:
1. Laser spectroscopy of the light-sensitive materials and their
applications (leader of the project Prof. J. Kikas)
2. Nanostructured materials (Dr. K. Haller, Dr. A. Rosental from
2005)
3. Biophysical elementary processes and their dynamics (Prof.
A. Freiberg)
4. Radioactivity and radiation dose in Estonian environment (Dr.
E. Realo)
5. Theory of the fundamental structure of the matter (Prof.
V. Hižnjakov)
6. Laser physics and laser-optical technologies (Prof. P. Saari)
7. Fundamental phenomena in wide-gap materials and their
prospects of application (Prof. A. Lushchik).
The present Report has also been built up according to these topics.
In 2004 (2005), the Institute has had a possibility of using also the
following finances (MEEK): financing of the infrastructure 4.8 (5.1);
Estonian Science Foundation grants in total 5.3 (6.7); financing of
the Estonian Centre of Excellence 3.4 (3.0), and a number of
industry and non-profit organisations contracts. In 2005, the the
Institute’s science financing line was complemented by 4.0 MEEK of
base financing, which can be used by the director for introducing new
investigation trends and for supporting new topics, for developing the
infrastructure or for co-financing international and internal contracts.
One of the most essential factor of the algorithm of the research
and developmental institution’s base financing amount is the number
of scientific publications by the institution’s researchers reflected in
the ISI data base. As the number of the publications with the
participation of the Institute’s researchers has in recent years indicated
some lowering tendency, we decided to stimulate our best authors
with the so-called publication bonuses. The first publications-results-
Institute of Physics • 15
based summaries were made in 2005 and these are to be continued
also in future.
The total amount of money at the disposal of the Institute of
Physics in 2004 was 36.7 MEEK and in 2005, 40.3 MEEK. However, this does not comprise all the money used. In fact, it is not
possible to get an exact survey about the financing of all our research
works, as the travel grants of some projects, the research grants
abroad, etc. are often covered from the foreign research allocations.
The research results of the two years surveyed here have been
publicized in total in 246 publications, including 140 articles in preedited magazines. Our research fellows participated in 116 scientific
conventions, 89 of which were international. In total 235 reports
were presented (112 oral ones and 123 posters).
Some additional information about the Institute of Physics and
the contact requisites can be found from the web page
http://www.fi.tartu.ee/. Any direct contact with the institute is most
welcome!
Ergo Nõmmiste,
director
1. ORGANIZATION AND PERSONNEL
1.1. Structure
Institute of Physics,
University of Tartu
Riia 142, 51014 Tartu
Estonia
Phone: +372 7428 102
Fax: +372 7383 033
E-mail: [email protected]
http://www.fi.tartu.ee
18 • Biannual Report 2004/2005
1.2. Supervisory board
(The Scientific Council of the Institute)
1. Ergo Nõmmiste, PhD, director of the Institute (chairman)
2. Marco Kirm, PhD, research director of the Institute (vicechairman)
3. Ilmar Ots, PhD, senior researcher (elected vice-chairman)
4. Ene Ergma, DSc, member of the Estonian Acad. Sci., President
of the Parliament of Estonia
5. Arvi Freiberg, DSc, head of laboratory, prof., University of Tartu
6. Vladimir Hizhnyakov, DSc, member of the Estonian Acad. Sci.,
prof. emer., senior researcher
7. Raivo Jaaniso, PhD, senior researcher
8. Arvo Kikas, PhD, head of laboratory
9. Jaak Kikas, PhD, prof., University of Tartu
10. Rein Kink, DSc, senior researcher
11. Nikolai Kristoffel, DSc, prof. emer., University of Tartu
12. Henn Käämbre, DSc, assistant director of the Institute
13. Aleksandr Lushchik, DSc, head of laboratory, prof., University
of Tartu
14. Vitali Nagirnyi, PhD, senior researcher
15. Kaido Reivelt, PhD, director of studies of the Institute (from
01.06.2005)
16. Arnold Rosental, PhD, senior researcher
17. Peeter Saari, DSc, member of the Estonian Acad. Sci., head of
laboratory, prof., University of Tartu
18. Matti Selg, PhD, senior researcher
19. Ilmo Sildos, PhD, head of laboratory
20. Aleksei Treshchalov, PhD, head of laboratory
21. Tõnu Viik, DSc, vice-director of the Tartu Observatory
(Hudo Jõgi, PhD, assistant director of the Institute (secretary))
Organization and Personnel • 19
1.3. International Advisory Board of the Institute
Prof. Hans G. Forsberg, ex president of Royal Swedish Academy of
Engineering Sciences and of Council of Academies of
Engineering and Technological Sciences of Sweden
Prof. Rienk van Grondelle, professor of biophysics, the Free
University of Amsterdam, the Netherlands
Prof. Dietrich Haarer, professor of experimental physics, University
of Bayreuth, Germany
Prof. Maurice Jacob (chairman), former head of the Division of
theory of CERN, ex president of the European and French
physical societies, member of the advisory committee of “Physics
Today”, Switzerland
Prof. Tõive Kivikas, ex president of the company Studsvik and
Estinvest Foundation, Sweden.
1.4. Directorate
Director
Ergo Nõmmiste, PhD
+372 738 3039
e-mail: [email protected]
Research director
Henn Käämbre, DSc
(up to 30.06.2004)
Marco Kirm, PhD
(from 01.07.2004)
+372 742 8493
e-mail: [email protected]
Director of studies
Kaido Reivelt, PhD
(from 01.06.2005)
+372 7383 028
e-mail: [email protected]
20 • Biannual Report 2004/2005
Assistant director
Henn Käämbre, DSc
Assistant director
Hudo Jõgi, PhD
Managing director
Ülo Uibo
Chief accountant
Linda Paade
+372 742 8182
e-mail [email protected]
+372 742 8948
e-mail: [email protected]
+372 742 8133
e-mail: [email protected]
+372 738 3032
e-mail: [email protected]
1.5. Directorial Board
A regularly (once a week)-working deliberative assembly of directors
and heads of structural units on councelling current problems of the
Institute’s work.
1.6. Personnel
Senior, assistant staff and graduate students of scientific projects
Laser spectroscopy and applications of photosensitive materials
Kikas Jaak, prof., proj. leader,
PhD
Aarik Jaan, head of group, MSc
(0.5)
Kuznetsov Anatoli, researcher,
PhD
Laisaar Arlentin, senior
researcher, PhD
Mauring Koit, senior researcher,
PhD
Mändar Hugo, senior researcher,
PhD
Organization and Personnel • 21
Palm Viktor, senior researcher,
PhD
Rebane Karl, senior researcher
(0.5) prof. emer., DSc
Lukner Argo, MSc student
Renge Indrek, senior researcher,
PhD
Siimon Hele, researcher, PhD
Sild Olev, senior researcher, PhD
Sildos Ilmo, head of lab, PhD
Suisalu Artur, senior researcher,
PhD
Kiisk Valter, PhD student, MSc
Krasnenko Vera, PhD student,
MSc
Lange Sven, PhD student, MSc
Pärs Martti, PhD student, MSc
Marju Kleeman, MSc student
Visk Urmo, MSc student
Nanostructured materials
Rosental Arnold, senior
researcher, proj. leader, PhD
Aarik Jaan, head of group, MSc
(0.5)
Adamson Peep, senior researcher,
PhD
Avarmaa Tea, researcher, PhD
Jaaniso Raivo, senior researcher,
PhD
Kasikov Aarne, researcher, MSc
Kink Ilmar, senior researcher,
PhD
Konsin Peet, senior researcher,
(0.5) DSc
Lõhmus Ants, head of lab, PhD
Lõhmus Rünno, senior researcher,
PhD
Niilisk Ahti, senior researcher,
PhD
Saal Kristjan, researcher, MSc
Sammelselg Väino, prof., PhD
Sorkin Boris, researcher, PhD
Uustare Teet, senior researcher,
PhD
Tätte Tanel, PhD student, MSc
Tarre Aivar, PhD student, MSc
Floren Aare, PhD student, MSc
Kärkkänen Andrei, PhD student,
MSc
Kärkkänen Irina, PhD student,
MSc
Rammula Raul, PhD student,
MSc
Reedo Valter, PhD student, MSc
Kodu Margus, MSc student
Leinberg Martin, MSc student
Lobjakas Madis, MSc student
Paalo Madis, MSc student
Pärna Rainer, MSc student
Shulga Jevgeni, MSc student
Timusk Martin, MSc student
Vesi Urmas, MSc student
22 • Biannual Report 2004/2005
Vlassov Sergei, MSc student
Aidla Aleks, engineer, PhD
Asari Jelena, engineer
Gerst Alar, engineer
Kiisler Alma-Asta, engineer
Lurich Robert, laboratory
assistant
Plaado Margo, laboratory
assistant
Matisen Leonard, engineer
Ritslaid Peeter, engineer
Biophysical elementary processes and their dynamics
Freiberg Arvi, head of lab, prof.,
proj. leader, DSc
Ellervee Aleksander, researcher,
PhD
Kangur Liina, researcher, MSc
Leiger Kristjan, postdoc, PhD
Rätsep Margus, senior researcher,
PhD
Timpmann Kõu, senior
researcher, PhD
Pettai Hugo, PhD student, MSc
Radioactivity and dose in Estonian environment
Realo Enn, senior researcher,
proj. leader, PhD
Haas Mati, senior researcher,
PhD
Kiisk Madis, postdoc, PhD
Realo Küllike, head of lab, PhD
Isakar Kadri, MSc student
Aarik Lauri, MSc student
Koch Rein, engineer, PhD
Theory of the fundamental structure of the matter
Hizhnyakov Vladimir, senior
researcher, proj. leader, prof.
emer., DSc
Fedoseev Vladimir, senior
researcher, PhD
Järv Laur, researcher, PhD
Kaasik Helle, postdoc, PhD
Konsin Peet, senior researcher
(0.5), DSc
Kristoffel Nikolai, senior
researcher, prof. emer., DSc
Kuusk Piret, head of lab, DSc
Liivat Hannes, PhD student, MSc
Ots Ilmar, senior researcher, PhD
Rebane Inna, senior researcher,
PhD
Rebane Karl, senior researcher
(0.5), DSc
Organization and Personnel • 23
Rubin Pavel, researcher, PhD
Shelkan Aleksandr, researcher,
Saal Margus, researcher, PhD
PhD
Sherman Aleksei, head of lab,
Tehver Imbi, senior researcher,
DSc
DSc
Sild Olev, senior researcher (0.5), Boltrushko Vadim, PhD student,
PhD
MSc
Laser physics and laser-optical technologies
Saari Peeter, head of lab, prof.,
proj. leader, DSc
Jalviste Erko, researcher, PhD
Kink Margarita, researcher, PhD
Kink Rein, senior researcher, DSc
Maksimov Juri, researcher, PhD
Peet Viktor, senior researcher,
PhD
Reivelt Kaido, postdoc, PhD
Selg Matti, senior researcher, PhD
Stolovich Andres, senior
researcher, PhD
Treshchalov Aleksei, head of lab,
PhD
Shchemelev Sergei, PhD student,
MSc
Lissovski Aleksandr, PhD student,
MSc
Burak Sergei, MSc student
Savustjan Grigori, MSc student
Valtna Heli, MSc student
Anijalg Agu, engineer
Kilk Andrus, engineer
Kippasto Avo, engineer
Tsarenko Sergei, engineer
Tsubin Vladimir, engineer
Fundamental phenomena in wide-gap materials and
their prospects of application
Lushchik Aleksandr, head of lab,
prof., proj. leader, DSc
Babin Vladimir, researcher, PhD
Dolgov Sergei, researcher, PhD
Feldbach Eduard, senior
researcher, PhD
Kikas Arvo, head of lab, PhD
Kirm Marco, research director,
PhD
Kisand Vambola, postdoc, PhD
Kotlov Aleksei, researcher, PhD
Kudryavtseva Irina, researcher,
PhD
24 • Biannual Report 2004/2005
Kärner Tiit, senior researcher,
PhD
Käämbre Henn, assistant director,
DSc
Käämbre Tanel, postdoc, PhD
Lushchik Cheslav, senior
researcher, DSc
Maaroos Aarne, senior researcher,
PhD
Nagirnyi Vitali, senior researcher,
PhD
Nõmmiste Ergo, director, PhD
Ruus Rein, senior researcher,
PhD
Saar Agu, senior researcher, PhD
Zazubovich Svetlana, senior
researcher, DSc
Vasil’chenko Evgeni, senior
researcher, PhD
Issahanyan Vigen, PhD student,
MSc
Kooser Kuno, PhD student, MSc
Krasnikov Aleksei, PhD student,
MSc
Nakonechnyi Sergei, PhD
student, MSc
Galajev Semjon, MSc student
Makhov Aleksei, MSc student
Liblik Peeter, engineer
Savikhin Feodor, engineer, PhD
Supporting and maintenance staff
All-institute personnel and assistant staff at grant/contract projects
Tiismus Robert, leading
computer specialist
Koppel Hele-Mai, laboratory
assistant
Sikk Taimu, secretary
Sildos Liivia, office assistant
Soovik Hilja, engineer, PhD
Vesman Elmar, engineerconsultant, PhD
Book-keeping
Paade Linda, chief accountant
Saumaa Hannes, leading engineer
Library
Puusepp Tiia, head
Luik Anne, lawyer
Organization and Personnel • 25
Mechanics workshop
Tammik Heini, head
Ernits Inge, technician
Hani Gustav, polisher
Kivi Kalmer, locksmith
Kuusk Andrei, miller
Olev Karl, turner
Parmas Ilmar, locksmith
Rebase Valdek, welder
Tarus Tõnu, miller
Cryogenic service
Tomberg Vello, head
Vahi Jüri, engineer
Management office
Rand Anne, head manager
Johanson Ants, locksmith
Leppik Silvia, technician
Mägimets Rein, electrician
Otsa Vello, electrician
Segar Enno, driver
Toomsalu Jaan, electrician
Truus Endel, technician
Õunap Harri, locksmith
Estonian Nanotechnology
Competence Centre
History
In 2002 Estonian Government launched a Competence Centre
Programme aiming at “To increase competitiveness of Estonian
enterprises through strategic collaboration between industry and
academia”. Institute of Physics was one of the leaders in the
international consortium of public and private bodies that submitted
a proposal to carry out a research programme in the field of
nanotechnology and form a nanotechnology competence centre. The
proposal scored second highest ranking during the international
evaluation and was granted the requested funding by the Enterprise
Estonia. The next step in the programme – the launch of the Centres
– was, however, delayed considerable when one of the unsuccessful
applicants decided to challenge the results in the court, the
remarkable fact as being the first and so far fortunately the only
attempt to carry over such a destructive and sadly common practice in
business sector to (semi-)academic sphere.
Despite everything, Estonian Nanotechnology Competence
Centre (ENCC) was established in Dec., 2004 by companies Evikon
MCI, K-TEK Int. (USA), Maico Metrics, MikroMasch Eesti,
NexTech Supply, and University of Tartu. The main mission of the
Centre is to provide scientific and technology oriented research in the
field of nanotechnology. The research is funded by the partners of the
Centre, Enterprise Estonia and European Union. Dr. E. Nõmmiste
represents Institute of Physics in Centre’s Council and Dr. I. Kink in
Estonian Nanotechnology Competence Centre • 27
the Board. Nearly 30 Institute’s researchers, mainly from the groups
lead by Drs. R. Jaaniso, A. Rosental, and A. Lõhmus, are involved in
collaborative research works. The research plan for 3 years was
approved in Dec., 2004, and was partly revised in March, 2005 and
November, 2005 due to changes in state aid regulations. The programme consists of three major research directions: Nanotechnological Gas Sensors, Nanodevices, and Nanometrology. Each orientation is divided into totally ten sub-projects.
The Centre’s first year budget was 9 545 000 EEK (612 000
EUR), of which more than 90% were direct research costs. The team
consisted of 20–30 scientists (PhD or MSc level), 10–15 laboratory
assistants and 5 other staff members. The facilities included Partners’
infrastructures and other (rented) facilities if needed.
The first results
The Centre’s first scientific report was evaluated and fully approved
by international experts. The Centre’s research efforts should deliver
first applicable technologies in ca 3 years. Therefore, during the first
year a lot of attention was focused on development of experimental
facilities and initial tests of selected methods and materials. Thus,
within the first direction, the research groups have developed/
modified experimental set-ups to measure electric responses of thin
film gas sensor prototypes to varying gas-flow, temperature and
illumination conditions. Also, many different thin films were characterized by Raman spectroscopy, RHEED, XRD methods to select
the best candidates for sensors and to optimize their structure for the
best performance.
As an example of the research for the second and third research
directions some results obtained by T. Tätte’s research group on development of oxide nano-tips will be presented below. The objectives of
the project were:
x Development of a method to obtain alkoxide based precursors,
suitable for pulling nanometre level sharp oxide needles.
Figure 1. Schematics of the nano-tips’ fabrication method. (T. Tätte)
Figure 2. Sharpness of tin oxide nano-tips as a function of the
fabrication (i.e. pulling) speed. The sharpest tip radius is approximately 15 nm. (T. Tätte, K. Saal)
28 • Biannual Report 2004/2005
x Development of experimental facilities and methods for
pulling nano-tips from the viscous precursor.
During the first year a “pulling machine” was developed, which operation principle is shown on Fig. 1. A lot of effort was placed to
optimize the critical parameters of the precursor materials and the
fabrication method. Among other results was discovered that the
sharpness of the needles depends smoothly on the pulling characterristics as illustrated in Fig. 2. The tip radii of the needles were as small
as 15–20 nm, which is suitable for many nanotechnological
applications.
Future plans
The collaboration within the Centre’s framework is expected to
deliver new technologies for making thin film based gas sensors, novel
scanning probe tips and nanometrological calibration methods and
standards during the coming few years. At the end of 2007 a new call
for proposals will be announced and the Centre is optimistic to
initiate several new research projects with old and new partners.
Compiled by Ilmar Kink
2. GRANTS / CONTRACTS AND
CO-OPERATION PARTNERS
Foreign programs/grants/projects/contracts
1. Theoretical and experimental study of quantum dynamics and
localization in nonlinear crystal lattices (2000–2002, 2003–2004),
Estonia-USA NRC Twinning Program, Cornell University,
USA (Prof. A. J. Sievers) and IP UT (Prof. V. Hizhnyakov)
2. Untersuchung dynamischer biomolekularer Eigenschaften durch
57
Fe-Kernstreu-experimente mittels Synchrotronstrahlung (2001–
2003, extended), Medical University of Luebeck, Germany
(Prof. A. X. Trautwein) and IP UT (Dr. E. Realo)
3. Oxygen as a trace impurity in CaF2 (2002–2004), NATO Collaborative Linkage Grant PST.CLG.978807, IP UT (Prof.
A. Lushchik)
4. Nanotribology network (2002–2006), European Science
Foundation Programme, IP UT (Dr. A. Lõhmus)
5. CARIPLO Foundation fellowship (2003–2004), Landau Network, University of Milan, Italy (Prof. V. Hizhnyakov)
6. Medical Natural Sciences network (MedNatNet) (2003–2005),
EU Education and Culture (Socrates) ERASMUS 3 (Prof.
P. Mager, The Free University of Amsterdam), IP UT (Prof.
A. Freiberg, co-ordinator)
7. Optical characterization of metal dioxide films (2003–2005),
Research Grant II-03-019 at DESY, University of Hamburg; EU
Foundation – Research Infrastructure Action (Dr. I. Sildos).
30 • Biannual Report 2004/2005
8. Synchrotron-based electron spectroscopy (2003–2006), Nordic
Research Education Network for exploitation of synchrotron
radiation, NORFA/NordForsk; University of Bergen (Norway),
University of Uppsala (Sweden), University of Aalborg (Denmark) and IP UT (Estonia) (PI Prof. L. Saethre, Univ. of
Bergen)
9. MolSimu (2004–2008), European Co-operation Programme
COST-P13 (representative from Estonia – Dr. A. Lõhmus)
10. Doped metal-oxide nanomaterials for luminescence and gas sensing
applications (2005), Research Grant at Angstrom Nano Centre,
University of Uppsala; EU, Access to Research Infrastructure
Action of the Improving Human Potential Programme (Dr.
I. Sildos)
11. Time resolved single-molecule spectroscopy of terrylene in incommensurate biphenyl (2005), Research Grant IIc001119; EU, Programme LASERLAB-EUROPE (Dr. V. Palm)
12. Correlation between PDP firing voltage and luminescence properties of protective layer (2005), Co-operation Project with
SAMSUNG SDI (PI Dr. E. Feldbach)
13. Development of new secondary electron emission materials and
improvement of existing materials for PDPs using thin film technologies – pulsed laser, electron beam and atomic layer deposition
(2005–2006), Co-operation Project with SAMSUNG SDI (PI
Dr. M. Kirm)
14. Modelling of photosynthetic complexes under extreme conditions
(2005–2006), Estonian-French Co-operation Programme on
Research and Technology PARROT; CNRS/CEA, Saclay, Dr.
M. Marchi and IP UT, Prof. A. Freiberg
15. Ce-doped aluminium perovskite and garnet single crystal and single
crystalline film scintillators for high spatial resolution detectors
(2005–2007), INTAS Grant No. 04-78-7083, NATO Science
Programme (SfP) with collaboration partners from Czech
Grants/Contracts and CooperationPartners • 31
Republic (Prague, Turnov), Italy (Milan) Ukraine (Lviv, Kiev)
and Russia (Moscow); PI Dr. S. Zazubovich
16. Investigation of materials for radiation detection and lighting
applications (2005–2007), Grant No. EAP.RIG.981411, NATO
Programme “Security Through Science” (PI Dr. V. Babin).
Co-operation partners
Australia
Austria
Belgium
Denmark
Finland
France
Germany
Australian Nuclear Science and Technology Organization ANSTO (Materials Division)
University of Natural Resources and Applied Life
Sciences Vienna (BOKU) (Institute of Meteorology)
University of Liége, Institute of Physics (SUPRAS)
Czech Republic Institute of Physics (Lab of Luminescence), Prague CRYTUR Ltd Co., Turnov
Risoe National Laboratory Aalborg University (Institute
of Physics)
University of Helsinki (Lab of Inorganic Chemistry)
Technical University of Helsinki (Lab of Inorganic and
Analytic Chemistry)
University of Jyväskylä (Dept of Chemistry)
University of Oulu (Dept of Physical Sciences)
University of Turku (Dept of Applied Physics)
Tampere University of Technology (Surface Science
Lab)
Helsinki Institute for Physics (HIP)
CNRS/ CEA, Saclay Laser-Matter Interaction Centre
International Agency for Research on Cancer (Radiation
Group)
CNRS Bordeaux
University of Stuttgart (Institute of Theoretical Physics)
32 • Biannual Report 2004/2005
Hungary
Italy
University of Hamburg (Institute of Experimental
Physics, HASYLAB at DESY)
University of Regensburg (Institute of Applied Physics)
University of Jena (Institute of Theoretical Physics)
University of Erlangen-Nürnberg
University of Würzburg
Lübeck University (Institute of Physics)
Technical University of Chemnitz (Institute of Physics)
Max-Planck-Institute of Bioorganic Chemistry, Mühlheim
Max-Planck-Institute for Solid State Research, Stuttgart
Humboldt University, Berlin
Kiel University (Institute of Physical Chemistry)
Friedrich-Schiller-Universität, Jena
Gesellschaft für Schwerionenforschung (GSI),
Darmstadt
Great Britain University of Sheffield (Robert Hill
Institute of Photosynthesis,
Krebs Institute of Biomolecular Investigations)
University of Glasgow (Dept. of Biochemistry and
Molecular Biology)
University College, London
University of Oxford
Eötvös Lorand University (Dept of Organic Chemistry)
Institute for Solid State Physics and Optics, Hungarian
Acad. Sci., Budapest
University of Szeged (Dept of Physics)
Institute of Applied Physics, Florence (Lab of Laser
Spectroscopy)
University of Milan-Bicocca (Dept of Material Science)
Institute of Photonics and Nanotechnology, Trento
University of Messina
Grants/Contracts and CooperationPartners • 33
Japan
Japan Atomic Energy Research Institute
University of Hokkaido (RIES)
Kazakhstan University of Aktyubinsk
Almaty State University
Latvia
University of Latvia (Institute of Solid State Physics),
Riga
Institute of Solid State Physics, Riga
Lithuania
Institute of Physics, Vilnius
Vilnius University (Dept of Theoretical Physics)
Mexico
University of Sonora
The Netherlands University of Groningen (Materials
Science Centre)
University of Leiden
Norway
University of Bergen (Dept of Chemistry)
Russia
Lebedev Physical Institute, Moscow
Institute of General Physics, Moscow
Kirenski Physical Institute, Krasnoyarsk
Ioffe Physico-Technical Institute, St.Petersburg
University of St.Petersburg
Herzen State Pedagogical University, St.Petersburg
Ural State Technical University
Spain
University of Valladolid (Inst. of Electronics and
Telecommunication)
Universidad Autonoma de Madrid
Sweden
Lund University (Dept of Physics; Lab of Solid State
Physics;
MAX-Lab; Dept of Chemical Physics)
Lund Laser Centre (Division of Atomic Physics)
University of Uppsala (Dept of Physics; Ångström Lab)
Chalmers University of Technology (Dept of Applied
Physics), Göteborg
Royal Institute of Technology (Dept of Theoretical
Chemistry), Stockholm
34 • Biannual Report 2004/2005
Ukraine
USA
Institute for Scintillation Materials (ISMA), Kharkov
Lviv University (Lab of Luminescence)
Institute for Problems of Materials Science of the
National Acad. Sci. of Ukraine, Kiev
Cornell University (Dept of Atomic and Solid State
Physics), New York
Montana State University (Dept of Physics)
University of Hawaii (School of Ocean and Earth
Science and Technology)
3. RESEARCH HIGHLIGHTS
Difference fluorescence line narrowing –
an effective selective spectroscopy tool
for studies of complex molecular systems
Arvi Freiberg and Margus Rätsep
Great progress has been made in optical spectroscopy of impurity
centers in solids since the development more than 30 years ago of two
basic spectrally selective techniques: fluorescence line narrowing
(FLN) [1] and spectral hole burning (HB) [2]. Clearly, advent of
lasers was the main prerequisite of this advance.
Spectral HB involves a quasi-monochromatic laser light to
selectively bleach a narrow isochromat of chromophores or aggregates
of chromophores within an inhomogeneously broadened absorption
band. Hole burning occurs when resonance with electronic transitions of the chromophore is destroyed by photo-induced changes of
the chromophores electronic states, by structural rearrangements of
the host environment, or both. The first mechanism is commonly
referred to as photochemical HB, while the second, as non-photochemical HB. It is worth noticing that non-photochemical HB is
typical for chromophores in amorphous matrices such as inorganic
and organic glasses, polymers, and proteins. The hole-burned
spectrum is obtained as the difference between the absorption spectra
taken before and after the bleaching process. It was soon realized that
although much more clear-cut than the bands measured by common
absorption spectroscopy, the shape of the HB spectrum does generally
36 • Biannual Report 2004/2005
not directly represent the homogeneous absorption spectrum, that is,
the selectivity of HB is limited. In the case of a single matrixembedded chromophore at low temperatures the homogeneously
broadened spectrum typically consists of series of narrow zerophonon lines corresponding to the purely electronic and electronvibrational (vibronic) absorption transitions between the two electronic states of the chromophore. Each zero-phonon line is accompanied from the high-energy side by a broad sideband due to coupling
of the electronic transition to the matrix phonons (Fig. 1). As a result
of this, even a monochromatic excitation within the zero-phonon line
will not ensure complete spectral selection. A comparably fraction of
molecules will simultaneously be excited via their phonon sidebands
leading to a complex HB line shape. In the case of weak vibronic
coupling the spectral holes can be burned only in the inhomogneously broadened purely electronic absorption region. The HB
spectrum then consists of two broad features called real- and pseudophonon sideband (PSB) holes, respectively, at energies higher and
lower relative to the narrow zero-phonon hole (ZPH) at the burn
laser frequency. As the names tell, the real-PSB represents phonon
transitions that are excited resonantly via zero-phonon lines, while
pseudo-PSB, those that are excited non-resonantly through their
phonon sidebands. There is also a weaker multi-phonon (multi-PSB)
contribution distributed on both sides of ZPH. It represents phonon
sidebands of zero-phonon lines associated with the pseudo-PSB holes.
A spectral distribution of ZPH depths measured at constant nonsaturating burn fluence results in the so-called ZPH action spectrum
or site distribution function (SDF in Fig. 1), which is a measure of
static inhomogeneous spectral broadening.
Similarly to HB in absorption, FLN spectroscopy employs monochromatic laser light to selectively excite emission from chromophores
within their inhomogeneously broadened ensemble. The resulting
line-narrowed fluorescence spectrum can again be related to its
underlying homogeneous spectrum. Spectral HB and FLN are thus
pre-burn
post-burn
SDF
' FLN
SDF
real-PSB
SDF
pseudo-PSB
multi-PSB
frequency
pseudo-PSB
multi-PSB
SDF
real-PSB
'A
Figure 1. Model difference fluorescence line narrowing ('FLN) and
hole burning ('A) spectra exposing their component spectra. Upper
part of the figure shows inhomogneously broadened site distribution
functions (SDF) before and after persistent spectral hole burning. A
contribution of photoproduct spectra is left out for clarity. See text
for further details.
Research Highlights • 37
complementary line-narrowing techniques, in the lowest approximations of theoretical models providing equivalent information about
photoactive material centers. In practice, however, there are differences related how the zero-phonon line and various phonon
sideband components are represented in the experimental spectra.
The shape of the homogneously-broadened spectrum of the twolevel impurity center in the low-temperature matrix is determined by
the density of phonon states of the matrix, weighted by the electron–
phonon coupling strength. The latter can be characterized by the total
dimensionless Huang-Rhys factor, S, which determines the mean
number of phonons absorbed or emitted upon the electronic
transition in the impurity center. The integrated intensity of the zerophonon line component divided by the intensity of the entire (zerophonon plus real-PSB) spectral profile is equal to exp(–2S).
Therefore, the HB spectrum where the real- and pseudo-PSB
components lie on opposite sides of the ZPH seem to allow a rather
straightforward analysis of the low-frequency phonon contributions
directly from the experiment. Yet, the high-energy side of the
experimental HB spectrum is normally distorted by the absorption of
HB products, which in the case of non-photochemical HB tend to
randomly redistribute within the whole span of SDF. Also, as can be
seen from Fig. 1, the limited width of SDF suppresses the highfrequency phonon part of the pseudo-PSB component spectrum.
Ignoring these aspects may lead to serious underestimation of the
actual Huang–Rhys factor. On the other hand, in FLN the real-,
pseudo-, and multi-PSB parts, all lie towards lower energy from the
zero phonon line. Counting of pseudo-PSB and multi-PSB parts
present in experimental spectra now results in overestimation of the
Huang–Rhys factor. However, far more serious obstacle in this case is
the excitation laser scattering (Rayleigh scattering) artifact that usually
totally obscures the zero-phonon line.
These shortcomings of FLN and HB techniques are well recognized. Various solutions to handle the problem, typically exploiting
38 • Biannual Report 2004/2005
optical saturation of zero-phonon transitions due to vastly different
absorption cross-sections of the zero-phonon line and of its phonon
sideband, have been proposed (see reviews by Rein Avarmaa and Jaak
Kikas in [3], and references therein). Among the most promising
techniques, dubbed here as difference fluorescence line narrowing
('FLN) spectroscopy, is the one that uses persistent spectral HB to
gain selectivity. As the difference between the pre-burn and post-burn
absorption spectra yields the persistent HB spectrum, that between
the emission spectra produces the 'FLN spectrum. The 'FLN
spectrum thus shows the contribution of the emission that has been
lost due to hole burning, that is, it corresponds to the sites or states
that were burnt out during irradiation. The utility of this technique
has previously been demonstrated on vibronic transitions of some
organic impurity centers in glassy matrices [3, 4]. We have recently
extended this method on delocalized exciton spectra in
photosynthetic antenna pigment-protein complexes [5–7].
Shown in Fig. 2 are a series of common FLN spectra (curves a to
e) measured at different excitation fluences and the 'FLN spectrum
((a-e)/2) of excitons in FMO antenna bacteriochlorophyll-protein
complexexes isolated from the green photosynthetic bacterium
Chlorobium tepidum. The total spectrum on inset demonstrates one of
the greatest advantages of 'FLN with respect to the FLN spectrum:
the zero phonon line in difference spectrum is virtually free from
excitation laser scattering artifact. This allows a clear-cut determination of the above-described homogeneous spectral parameters from
purely electronic emission transitions for the first time. A decisive
factor in this achievement (apart from successful efforts to minimize
scattered laser light by controlling the quality of the sample, special
design of the cuvette holder, spatial filtering of the excitation beam
etc.) was the usage of modern technology based on CCD camera that
by simultaneous recording of the whole spectrum maximizes the
signal-to-noise ratio.
' FLN
827.1 nm
a
FLN/ ' FLN
b
c
d
826 830 834
e
(a-e)/2
826
830
834 838 842
Wavelength (nm)
Figure 2. Fluorescence line-narrowing spectra of the FMO complex
at 4.2 K. The five FLN spectra from top to bottom correspond to
excitation light fluences at OE=OB=827.1 nm of 1.6 (virtually no hole
burning), 4.8, 8.0, 28 and 126 mJ/cm2. The lowest curve shows a
difference between the initial and the 126 mJ/cm2 post-burn
fluorescence spectra, the 'FLN spectrum. The spectra are magnified
in order to bring out the sideband details. An overview of the 'FLN
spectrum is shown on inset.
Figure 3. Phonon sidebands of 'FLN spectra of bacteriochlorophyll
a molecules in different surroundings. See text for details.
Research Highlights • 39
Yet another advantage of the 'FLN technique can also be noticed
on Fig. 2. There is a shoulder near 837 nm in FLN spectra that can
be due either to low energy intramolecular modes of the photoactive
bacteriochlorophyll a pigments or by non-resonantly excited
fluorescence of a residual reaction center core complex, not subject to
bleaching at OE=827.1 nm. The 'FLN spectrum indicated by (a-e)/2
clearly favors the second choice, at the same time revealing the actual
contribution of intramolecular modes around 839–841 nm. This
increased selectivity is an immense gain when complex systems like
photosynthetic antennas or polymers are studied.
The phonon sidebands of line-narrowed spectra are considered to
reflect local dynamics of the matrix directly surrounding the probe
chromophores. By virtue of the above properties of 'FLN spectra,
this technique can be very useful for such dynamics studies.
Demonstrated in Fig. 3 are phonon sidebands of 'FLN spectra of
bacteriochlorophyll a molecules in several glassy matrices of protein
and polymeric origin at 4.2 K. We notice that the probe molecules
are well isolated from each other in all samples, except that in the
LH2 antenna complex (represented with blue curve in Fig. 3) where
the pigments are electronically strongly coupled and excitons are
formed upon excitation by light.
As can be seen from Fig. 3, the isolated molecules all show similar
spectra with a distinct maximum that is red-shifted by ~20 cm–1
relative to the zero phonon line, despite evident differences in the
local structure of the surroundings of probe molecules: a protein
matrix of predominantly E-sheet conformation in FMO complexes
(green curve, the same as curve (a-e)/2 in Fig. 2), a protein matrix of
D-helix conformation in LH2 complexes (blue), and a polymer
(polyvinylbutyral) glass (black). This maximum, the so-called boson
peak, is characteristic to phonons in amorphous solids and represents
an increased density of phonon states over that of classical Debye
density in perfect crystals. There, however, has so far been no
consensus about the physical origin of the boson peak. The shape of
40 • Biannual Report 2004/2005
the sideband of the 'FLN spectrum of LH2 antenna complexes (blue
curve) appears even more challenging. According to [6–8], this
spectrum is due to large-radius excitonic polarons whose wavefunction is localized on a number (5–8, depending on the system)
bacteriochlorophyll a molecules. A reduced interaction with intramolecular vibrations around 200 and 350 cm–1 is a clear evidence of
delocalized nature of the exciton polaron wavefunction. Strong
coupling of the exciton to the pair-wise inter-pigment vibrational
modes has been proposed as probable cause of the sideband transformations observed (relative to the spectra for isolated pigments) [7].
There in LH2 complexes is also a small amount of dysfunctional
bacteriochlorophyll a molecules that are unable for fast intermolecular energy transfer (drawn in red on Fig. 3). Their spectra are
almost indistinguishable from the ones in polymer matrix. This once
again implies that the molecular probes (at least such big as bacteriochlopylls) in amorphous matrices actually sense not the direct
surroundings but a much more extended space around them.
REFERENCES
1. A. Szabo, Phys. Rev. Lett. 25, 924–926 (1970).
2. A. A. Gorokhovskii, R. K. Kaarli, L. A. Rebane, JETP Lett. 20, 474-476
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37–48 (2005).
8. G. Trinkunas, A. Freiberg, J. Luminescence 112, 420–423 (2005)
Research Highlights • 41
Probing anomalous ZZJ and ZJJ couplings
in e+e– o ZJ with polarized initial beams
Ilmar Ots and Hannes Liivat
Our present theory of the fundamental interactions of the elementary
particles – the Standard Model (SM) – is phenomenologically
successful. At present the SM is in consistence with all acceleratorbased experiments. However, several fundamental questions remain
unanswered by the SM. Obviously, as a theory in its present form,
the SM is not satisfactory and it is widely expected that there exists
more fundamental New Physics (NP) beyond the SM, with new
characteristic high mass scale.
The most straightforward method for searching NP would be the
production of NP particles. Such a scenario for visualizing NP
experimentally is beyond the reach of current accelerators and can be
carried out only at future colliders. More indirect ways to investigate
NP are based on observation of small departures from the SM
predictions in processes, where the external particles are ordinary SM
ones, and NP effects can arise only from non-standard interactions. It
is believed that one of possible such sources of NP may be the
existence of anomalous gauge boson self-couplings. Motivated by this
possibility such couplings have been theoretically extensively
investigated and experimentally tested. Though to date no evidence of
anomalous gauge boson self-couplings has been established, the
bounds obtained at the CERN e+e- collider and at the Fermilab
Tevatron are comparatively weak [1]. It is also clear that the current
accelerators cannot provide sensitivities which would be considerably
better than the ones already achieved. However, the study of gauge
boson self-interactions is an important item in the physics of the
planned next generation colliders. As soon as the proposed high
energy colliders start running, a dramatic improvement on the sensitivity of the experiments to nonstandard couplings is expected.
42 • Biannual Report 2004/2005
Among gauge boson self-couplings the most sensitive probes of NP
are provided by the couplings of three neutral gauge bosons. Among
processes to which such couplings could contribute are the neutral
gauge boson productions in e+e- annihilation. The processes (e+e- o
ZJ, ZZ, JJ) are particularly interesting and promising in various
aspects. The final gauge bosons are easy to detect experimentally,
while the theoretical structure of the processes provides clean and
unambiguous test of the SM electroweak interactions. From the other
side, the SM predicts here no tree level (the lowest order) selfcouplings and the higher order loop level corrections are vanishingly
small. Therefore, the precision measurements of these processes can
without ambiguities be compared with the SM predictions and any
deviation from these can be considered as contributions from
anomalous couplings [2].
A future e+e- International Linear Collider (ILC), operating in the
wide energy range up to about 1 TeV and designed with high
luminosity, provides an excellent discovery potential. An additional
advantage of the ILC is the possibility to have at it both initial beams
longitudinally polarized. Since by using spin rotators the longitudinal
polarization (LP) can be converted into the transverse polarization
(TP), another powerful tool of the ILC will be available – the use
alongside with longitudinally polarized beams also transversely
polarized ones. Due to these possibilities, the roles of polarizations,
especially the role of TP in the process with the possible anomalous
parts of couplings have attracted noteworthy attention in recent years.
A considerable part of these investigations is constituted by the ones
considering the LP and TP effects in the aforementioned processes,
particularly in e+e- o ZJ [3]. However, the studies connected with
the roles of LP and TP in searching anomalous couplings are yet far
from being exhaustive.
The aim of our investigations [4,5] was to calculate and analyse
the possible corrections of anomalous ZZJ and ZJJ couplings to the
spin orientation of the Z boson in the process e+e- o ZJ with longi-
Research Highlights • 43
tudinally and transversely polarized initial beams and with accentuation of the roles of LP and TP in disentangling the contributions
from different couplings – SM, ZZJ and ZJJ.
In most papers the spin-related studies have been carried out by
employing the helicity basis. The method of summing the Feynman
diagram with definite helicities of initial and final particles has proved
to be a powerful tool for describing the spin polarization phenomena.
However, quite often one can reach the desired results comparatively
easily by using other methods. The method we followed is the one
that uses in the squared amplitude of the process the relativistic spin1 density matrix, obtained by applying the Lorentz boost to the nonrelativistic one. In this case the squared amplitude is proportional to
the probability that the spin orientation of the Z boson is described
by the density matrix determined by the given rest frame polarization
vector and alignment tensor, and it is not a difficult task to deduce
from the squared amplitude the expressions for the actual spin
polarization vector ti and the alignment tensor tij of the Z boson. A
detailed description of the method can be found in [6].
By exploiting the method described, we found the analytical
expressions for the S (the part of the squared amplitude, independent
of the Z boson spin orientation parameters) and for the polarization
vector ti and alignment tensor tij of the final Z boson from e+e- o ZJ
with LP and TP initial beams and in the presence of anomalous ZZJ
and ZJJ couplings. In our calculations we limited ourselves to the
lowest order approximation, linear to the anomalous couplings. In
this approximation the process is described by two SM Feynman
diagrams and by two diagrams with the anomalous vertices and for
anomalous couplings effects only the interference of the SM and
anomalous couplings amplitudes are taken into account. General
expressions for anomalous ZZJ and ZJJ vertices have been given in
[7]. In the CP-conserving case (which we presumed) both of these
couplings are parametrized in terms of two form-factors, which are
restricted by unitarity conditions at high-energy: h3Z, h4Z for ZZJ and
44 • Biannual Report 2004/2005
h3J, h4J for ZJJ couplings. The evaluation of needed expressions is
quite routine, based on using the Lorentz boosts and the trace
techniques for the Dirac spinors with the longitudinal and transverse
components of the electron and positron polarization vectors. In the
calculations, the electron mass has been taken negligible as compared
to the energy scale of the process. The final expressions have been
given in the centre-of-mass system, which coincides with laboratory
frame in actual experiments.
By the analytical expressions for the polarization vector and
alignment tensor the spin orientation of the Z boson from e+e- o ZJ
with LP and TP beams and in the presence of possible anomalous
ZZJ and ZJJ couplings is fully described. The orientation of the
Z boson is transferred to the angular distribution of its charged
leptons decay products. As a consequence, one can put limits to the
anomalous couplings (to the values of form-factors hiZ and hiJ) by
probing the Z boson spin orientation through the measuring of the
shape of the Z boson lepton decay spectrum.
We do not give here the calculated analytical expressions for the
LP- and TP-dependent contributions to the Z boson spin orientation.
These expressions, especially the ones describing TP-dependent part
of the Z boson alignment tensors, are not very simple. However,
these expressions have a structure from which their features can easily
be learned. In what follows we give the general features of the
LP- and TP-dependent contributions from SM, ZZJ and ZJJ which
can be deduced from the expressions.
1) All contributions from the anomalous couplings vanish at the
threshold of the process.
2) All anomalous contributions vanish when the Z boson is emitted
in or against the direction of the initial electron.
3) Unlikely to LP contributions, the TP contributions are different
from zero only when both the electron and the positron are
simultaneously transversely polarized.
Research Highlights • 45
4) Differently from the LP-dependent contributions, the different
couplings (SM, ZZJ, ZJJ) do not give TP-dependent contributions to all quantities calculated, i.e. to S, ti and tij . Only the
anomalous ZJJ couplings contribute the TP-de-pendent part to all
of these quantities. The SM does not contribute to ti and, on
contrary, the ZZJ couplings contribute only to ti . This feature
could be very helpful for disentangling the contributions from
different (SM, ZZJ, ZJJ) couplings.
5) In absence of TP, the contributions to the process depend on the
coupling constants and on the beam LP parameters only through
the common factors in front of various types of couplings. Due to
this, LP does not enable any measurement of the parts of couplings which are inaccessible with unpolarized beams. By changing
the values of the LP parameters one can substantially enhance the
sensitivities to one or other part of couplings which, however, at
least in principle, are measurable also in the case of unpolarized
beams.
6) Contrary to the LP contributions, the TP contributions are not
factorized in such way and as a consequence, TP can enable the
measurements which are not accessible with LP or unpolarized
beams.
7) TP provide the theory with extra directions. Thanks to the TP
vectors, the Z boson polarization vector ti obtains additional,
generally out-of-reaction-plain components and new alignment
axes are added to the spin orientation tensor tij.
Some of these features (feature 1 and feature 3) have been noticed
earlier. However, by using the fully analytical expressions for the
contributions, all their properties can be more clearly and explicitly
demonstrated.
To get a feeling about possibilities for using the properties of the
LP and TP contributions for testing the SM and NP, we proceed
with an example. Since the SM generates no TP-dependent terms in ti
46 • Biannual Report 2004/2005
(feature 4), any such term has to be from the anomalous couplings
contributions. Due to the ZZJ and ZJJ TP-dependent contributions
to the Z boson polarization vector, the latter obtains additional part
(feature 7), which generally lies not on the reaction plain. As a conesquence, the whole Z boson polarization vector (unlikely to the ti from
LP or from unpolarized contributions) is outside the reaction plain.
Hence, the existence of the angle between the Z boson polarization
vector and the reaction plain indicates the anomalous self-couplings
contributions from the transversely polarized initial beams. Let us for
concreteness and simplicity restrict ourselves to a very special case.
Firstly, we take only one of the anomalous couplings (h3J) different
from zero with the value h3J=0.001 at the centre-of-mass energy 500
GeV. Secondly, for choosing the degrees of polarization we depart
from the values of the longitudinal polarizations foreseen in the base
line design of the ILC (Le-=0.8, Le+=0.6) and assume a 100%
efficiency of spin rotators, i.e. we take the values of the transverse
polarizations to be 7e-=0.8 and 7e+=0.6. Thirdly, we take the TP
vectors of e- and e+ to be perpendicular to each other. Then, in the
case when the Z boson is emitted in the directions perpendicular to
the electron momentum, D=2o, which would be certainly within the
sensitivity reach of the ILC.
In conclusion, our papers provide a set of expressions which can
be used to constrain anomalous couplings between three neutral
gauge bosons.
Our investigations were partly supported by ESF grants Nos.
4510 and 6216.
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D0 Collaboration, S. Abachi, et. al., Phys. Rev. D 56 (1997), 6742;
B. Abbot, et. al., Phys. Rev. D 57 (1998), R3817.
Research Highlights • 47
2. G. J. Gounaris, J. Layssac, F. M. Renard, Phys. Rev. D 67 (2003),
013012.
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(2004), 346.
5. I. Ots, H. Uibo, H. Liivat, R.-K. Loide, R. Saar, Possible anomalous
ZZJ and
ZJJ couplings and Z boson spin orientation in e+e- o ZJ: the role of
transverse
Polarization, Nucl. Phys. B (accepted).
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(2000), 90.
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(1987), 253.
Cuprate superconductivity characteristics
on the doping scale. A simple model
Nikolai Kristoffel
The present article reflects in some extent the elaboration of a simple
model by the author and Pavel Rubin which describes qualitatively
the behaviour of cuprate superconducting characteristics on the whole
doping scale. This model is based on the electron spectrum of a
charge transfer insulator essentially modified and evolving with the
hole doping. Cuprates belong to strongly correlated compounds and
the doping separates in them the defect subsystem bearing the
introduced carriers from the itinerant background. Interaction of
these electronic subsystems is considered as the decisive channel for
the superconductivity of cuprates in the model under consideration.
Nearly 20 years have been passed from the Müller and Bednorz
discovery of the high temperature superconductivity in La2–xMxCuO4
48 • Biannual Report 2004/2005
(M=Sr, Ba). A huge experimental, theoretical and technical research
on cuprates and relative compounds has been started and continues.
A number of highly valuable results and conclusions have been
obtained. However, the central problem of the nature of cuprate
superconductivity remains elusive. Various refined and deepgoing
approaches have not given decisive inferences. For this reason the
author has proposed another way. A very simple, partly postulative,
but plausible model of cuprate superconducting functionality has
been developed. It uses only gross features known from numerous
experimental and theoretical works. The outcome of the model is
expected to serve a phenomenological framework for embedding
more throughout theories on enlightened physical background.
Our model reflects the two-component scenario [1] of cuprate
superconductivity. Its essence consists in that a “defect-polaronic”
subsystem bearing doped holes is functioning besides the itinerant
valence band electrons. The model has been started in [2,3] and at
present [4–6] the defect subsystem is described by two subbands (D)
(“hot”) and (E) (“cold”) to distinguish the different functioning of the
S S
(S,0) and ( , )-type regions of the momentum space. These bands
2 2
are supposed to be gapped from the mainly oxygen itinerant band (J)
until the progressive doping brings them into overlap. This overlap
dynamics of normal state gaps opens a novel source of critical doping
concentrations on the doping phase diagram.
At the same time such a reorganisation of the spectrum opens a
novel possible pairing channel by the interband pair transfer between
the defect and itinerant states. The interband mechanism of superconductivity has been known for a long time. High transition
temperatures can be reached on this way out of exotic conditions.
Intersection (interference) of various bands at the Fermi energy is the
prerequisite for its functionality [7,8]. In cuprates the doping
procedure seems to prepare such conditions in the actual doping
region. The interest for the two-band superconductivity has been
Research Highlights • 49
especially grown with the recent discovery of a new high-Tc superconductor MgB2. In magnesium diboride which is a two-gap system
the interband pairing channel plays a remarkable role [9]. The twoband superconductivity model has been investigated in the Institute
of Physics extensively [7].
The theoretical description of the model under consideration
where the pairs built up from the particles of the same band are
scattered between the defect and the itinerant bands can be performed in a standardized manner [2,3,7]. The central term in the
Hamiltonian describing the multiband pairing is expressed by
W
¦ ¦¦ aV
VV
'
& & &
, ' k ,k ' q
&
a & & a & & a &
k n V k q p V ' k ' q p V ' k 'n
with the creation operators of electrons for fixed spins aV n in the
&
bandsV; q is the pair momentum. The interband coupling constant
W=V+U contains an electron-phonon (V) and Coulombic
contribution U. It is supposed that W>0. The interband scheme has
also the advantage that the pairing can be reached by the repulsive
interaction.
There are the following qualitatively different arrangements of the
band components and of the chemical potential (P). At the very
underdoping P is connected with the “cold” defect band bottom and
the normal state spectrum is fully gapped. At the doped hole
concentration p E theE–Joverlap starts andPenters the itinerant
band. The optimal doping region corresponds to the overlap of all the
band components being intersected by the chemical potential. At
extended overdopingPfalls out from theE-band and the conditions
for the interband pairing mechanism deteriorate. Correspondingly the
Tc vs doping curve, as also the supercarrier density ns and the superconducting gaps 'D ,J are bell-like, see Fig.1 and Fig.3. The characteristic ratios 2'V / k BT c for the superconducting gaps violate markedly
50 • Biannual Report 2004/2005
the Bardeen-Cooper-Schriffer universality. There are doping regions
where these ratios grow, while the transition temperature diminishes,
cf. [10,11]. In the two-band approaches such observed “anomalies”
are usual.
Progressive doping enhances the total concentration of the charge
carriers. On this background, however, the superfluid density
diminishes at overdoping. This problem [12] becomes naturally
solved by suppression of the interband pairing in this region. It must
be also noted that the bare normal state gaps does not manifest in
opening of fermionic gaps in the supefluid density because of the
interband nature of the pairing.
The excitation spectrum near the Fermi energy is determined by
the minimal energies of the quasiparticles ( EV ). In our model with
the doping-variable spectrum the nature of these energies changes
(H V P ) 2 '2V can be minimized by
with doping. Namely, if EV
H V P with the chemical potential in the corresponding band, the
low-energy spectrum is determined by the superconducting gap ' V .
In the opposite case the minimal value of EV represents in a natural
way the appearance of a pseudogap ' V (ps) which survives as a
normal state gap.
As the result, the manifestation of the four actual gaps of the
model in the “hot” channel ' V , J (ps) and ' D , J depend on the level
of doping. At expressed underdoping two pseudogaps can be
observable in general. If the cold defect subsystem is born as
nongapped, there remains only one (the larger) pseudogap ' D (ps).
The smaller pseudogap, if present, transforms at p E to the larger
(itinerant) superconducting gap, cf. [13]. The large pseudogap
(spectral hump) ' D (ps) extends until it is quenched in a slightly
overdoped region and crosses ' J , cf. [14,15].
At overdoping the spectrum is determined by both superconducting gaps. Spectrally the smaller superconducting gap (also in
presence of a pseudogap) manifests itself in an additional density on
the wings of the spectral hole due to the larger gap ( ' J or ' D (ps)).
Research Highlights • 51
According to our model the pseudogap can be considered as a
precursor of the superconducting gap on the doping scale, but not on
the energy scale. Experimentally one sees [10,11] in the normal state
the gap features at the phase diagram points, where in the superconducting state one observes the superconducting gap. This corresponds exactly to the result of our model.
The direct metallization of the cold subsystem is reached at p E .
The hot defect subsystem metallizes near the optimal doping. A
common mixed Fermi liquid is there built up. One expects a normal
state insulator to metal transition at this composition in agreement
with the observations [16]. It is also known that in infrared the
manifestation of the defect subsystem becomes here suppressed in
favour of a free carrier Drude peak [17].
In this manner the present model reproduces qualitatively the
observed behaviour of cuprate energetic characteristics on the doping
scale and relations between various gaps [10]. The presence of two
pseudogaps at underdoping has been observed recently for some
systems [12].
A plausible parameter set has been used to illustrate these results in
Fig.1. For a “typical” cuprate the Tc | max | has been adjusted to
p=0.16. For the calculation of various thermodynamic characteristics
a Ginzburg-Landau type expansion of the free energy of the model in
&
4-th order of the two order parameters, (T–Tc) and q has been
performed in collaboration with Teet Örd. The mixed nature of the
order parameters of the two-component superconductor leads to the
appearance of the “soft” and “rigid” components of superfluid wave
functions governed by different coherence scales [18]. The soft
coherence length behaves critically at Tc and the corresponding order
parameter component determines both superconducting gaps. The
other rigid coherence length behaves noncritically and describes a
periodic spatial coherence wave.
52 • Biannual Report 2004/2005
0.04
2
1
eV
0.03
3
0.02
4
0.01
5
0.00
0.00
0.05
0.10
0.15
0.20
0.25
0.30
p
Figure 1. Doping dependence of the gaps and Tc (5). 1; 2 – the small
and the large pseudogap. 3; 4 – the superconducting gaps of the
defect and the itinerant subsystem.
The superconductivity playground CuO2 in-plane coherence length is
shown in Fig.2 [19]. This “valley profile” nonmonotonic curve agrees
with the recent experimental result [20] where ] has been measured
on the whole doping scale. This result may be qualified as being
expected – weakly coupled pairs have larger dimensions. The second
c-axis critical field H c 2 (0) shows a well expressed maximum, as also
the condensation energy and the superfluid density show (Fig. 3). In
the present model the strength of the pairing and the phase coherence
develop and vanish simultaneously in accordance with the
conclusions in recent experimental investigations [12,13,21,22].
Research Highlights • 53
[/[0.15
3
a
2
1
[(A)
0
300
b
200
100
0
0.00
0.05
0.10
0.15
0.20
0.25
0.30
p
Figure 2. The CuO2 plane coherence length on the doping scale (a)
and the experimental result of [20] (b).
ns 0.040
16
0.035
14
0.030
12
0.025
10
0.020
8
0.015
6
0.010
4
0.005
2
0.000
0.00
0.05
0.10
0.15
0.20
0.25
mab/m0
0
0.30
p
Figure 3. The supercarrier effective mass theoretical dependence
(dashed line) on doping and the supercarrier density (solid line).
54 • Biannual Report 2004/2005
The paired carrier effective mass ( xm0 with m 0 of the free electron
mass) doping dependence [23], not been obtained earlier to the
author best knowledge, is given in Fig. 3. The overall m ab reduction
with doping reproduces the well-known trend to restore the Fermiliquid behaviour of the superconducting carriers. The magnetic
penetration depth ( O )is determined by the ratio pn s / x . According
to our calculations the strong nonmonotonic dependence of the
supercarrier density overwhelms here. This leads to a O 2 curve with
an expressed maximum in agreement with numerous experimental
findings [12, 21, 22].
The transition temperature isotope effect in cuprates is very
specific: its characteristic exponent D is small where the transition
temperature is remarkable [24] and vice versa. The explanation of this
trend is given also by the interband nature of the pairing [7,18]. A
relatively small contribution (V/W) of the interband electron-phonon
pairing, which is inverse proportional to the active vibration mass can
serve remarkable D -s for small Tc -s. Roughly, Tc in the present
model is large where distinct exponential coefficients minimize the Tc
(electronic) scale quenching. On the contrary, D is determined by
these terms, i.e. it is larger for dopings with relatively small Tc -s. The
two-component scenario explains also the presence of a critical and
noncritical relaxation channel in cuprates [25].
In this manner the present model describes qualitatively the
behaviour of various cuprate superconductivity characteristics on the
whole doping scale in an unified approach. The simplicity of the
model allows wide freedom to fill it in with precised assumptions,
improvements and quantitative content. We believe that cuprate
superconductivity must be traced on a spectrum prepared by doping
with the essential participation of the interband mechanism in the
pairing.
The appointments that high superconductivity temperatures can
be reached in systems where numerous (two) bands interface near the
Fermi energy become even more actual.
Research Highlights • 55
The author is grateful to P.Rubin and T.Örd for a long-running
collaboration.
This work was supported by the Estonian Science Foundation
grant No 6540 and continued the work done under grant No 4961.
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F. Venturini et al., Phys. Rev. Lett. 89, 107003 (2002).
P. Calvani, Phys. Status Solidi b 237, 194 (2003).
T. Örd, N. Kristoffel, Phys. Status Solidi b 216, 1049 (1999).
N. Kristoffel, T.Örd, P.Rubin, cond-mat/0504431 (2005).
H. H. Wen et al., Europhys. Lett. 64, 790 (2003).
J. T. Tallon et al., Phys. Rev. B 68, 180501 (2003).
T. Schneider, Physica B 326, 283 (2003).
N. Kristoffel, P.Rubin, cond-mat/0506317 (2005).
N. M. Plakida, High-Temperature Superconductivity, Springer, Berlin,
1995.
T. Örd, N. Kristoffel, Physica C 331, 13 (2000).
56 • Biannual Report 2004/2005
How small a packet of photons can be made?
Peeter Saari
In common non-relativistic quantum mechanics electron wave
function can, in principle, shrink into a point at the expense of
correspondingly large momentum uncertainty and energy. This is not
the case for photon, although solutions of the equations of electromagnetic field can be considered as photon wave functions, as it has
been known since 1930.-ies. However, when dealing with narrowband (nearly monochromatic) photon fields, localizability of a photon
wavepacket is merely an academic problem.
Recent developments in ultrafast and quantum optics and
corresponding applications deal with ultrawideband (few- and subcycle) pulsed photon states. Thus, the question – how small a packet
of photons can be made? – needs an elaborated treatment. Although
the photon wave function in the position space was introduced
already in 1930 by Landau and Peierls [1] the concept was found to
suffer from inherent difficulties that were not overcome during the
century (see review [2]). The common explanation presented in
textbooks (e.g.,[3, 4]) may be summed up as follows: (i) no position
operator exists for the photon, (ii) while the position wave function
may be localized near a space-time point, the measurable quantities
like the electromagnetic field vectors, energy, and the photodetection
probability remain spread out due to their non-local relation with the
position wave function.
However, recently both of these widely-espoused notions were
questioned and, particularly, Bialynicki-Birula [5] showed that the
statement “even when the position wave function is strongly concentrated near the origin, the energy wave function is spread out over
space asymptotically like r –7/2 „ (citation from [4], p.~638) is incorrect
and that both wave functions may be strongly concentrated near the
origin. He demonstrates, on one hand, that photons can be essentially
Research Highlights • 57
better localized in space – with an exponential falloff of the photon
energy density and the photodetection rates. On the other hand, he
establishes that certain localization restrictions arise out of a mathematical property of the positive frequency solutions which therefore
are of a universal character and apply not only to photon states but
also hold for all particles. More specifically, it has been proven in the
Letter [5] for the case of spherically imploding-exploding one-photon
wavepacket that the Paley-Wiener theorem allows even at instants of
maximal localization only such asymptotic decrease of the modulus of
the wave function with the radial distance r that is slower than the
linear exponential one, i.e., anything slower than ~exp(–r/l) where l
is a constant. The latter is what the Paley-Wiener theorem says about
a function whose Fourier spectrum contains no negative frequencies.
We have demonstrated [6] that one-photon wave functions (or
more generally – N-photon Fock states) of a specific spatial mode
type can break the localization restriction and exhibit the linear
exponential and even faster (Gaussian) falloff with the distance. Yet,
there is no contradiction either with the result of Ref. [5] or with the
Paley-Wiener theorem, since the wave functions are cylindrical and
exhibit an exceptionally strong localization in two dimensions out of
three. Our treatment involves a “technology transfer” in the sense
that in order to tackle the problem belonging to quantum electrodynamics, we make use of results obtained recently in the study of the
so-called nondiffracting localized solutions to the classical wave
equation (see [7–10] and references therein).
Without going into mathematical details, the procedure we used
was as follows. We took an appropriate localized-wave-type solution
to the scalar wave equation and build a Hertz vector of optional
direction (polarization) from it. By making use of the circumstance
that electromagnetic field vectors can be deduced from the Hertz
vector, we expressed the energy wave function of a N-photon number
state of the field and calculated its asymptotic dependence of the
58 • Biannual Report 2004/2005
energy spatial distribution on the radial distance r o f from the
wave axis.
As the first example leading to a stronger localization that one
might expect from the Paley-Wiener theorem we considered the
photon field where the Hertz vector is directed along the axis z (any
other orientation gives similar results) and its strength is given by the
scalar function of space and time [8]
< ( U , z ,W )
exp§¨ k 0
©
U 2 ' iW 2 ·¸
U ' iW 2
¹ e ik0 z .
2
(1)
This expression describes a simple cylindrical pulse modulated
harmonically in the axial direction and radially converging to the axis
(when the time variable ct { W 0 ) and thereafter (when W ! 0)
expanding from it, the intensity distribution resembling an infinitely
long tube coaxial with the axis z and with a time-dependent
diameter (see Fig. 1). The length parameter determines the radial
profile of the function at the instant t = 0. With this function the
energy (or photodetection probability) distribution turns out to
possess the following asymptotic falloff with the radial distance
| F ( U o f, z , W
1
>
@
0) | 2 a U 2 O( U 3 ) exp(2 U / l ) ,
(2)
is the characteristic length (or length unit). Thus,
where l k 0
while the photon is delocalized in the axial direction, its energy
density falloff in the lateral directions is exactly the linear exponential
one. Hence, a one-photon field derived from Eq.(1) serves as a simple
example where the localization in two transversal dimensions is
governed by different rules than localization in three dimensions
according to Ref.~[5].
Figure 1. The cylindrically converging-expanding wave given by
Eq. (1). Shown is dependence (a,c) of the real part and (b,d) of the
modulus of the wave-function on the coordinate z (increasing from
the left to the right) and on a transverse coordinate x = ± at two time
instants: (a,b) ct = 0 and (c,d) ct = l . Distance between the grid lines
on the basal plane (x,z) is l. The grey-scale plots of | (x,z,t)| are
normalized to “white” at the plot maximum, so that the “white” level
in the plot (d) is actually 5 times weaker than in plot (b). The grey
shading in plots (a) and (c) is a result of “lighting” used for better
revealing the relief of the surface.
Figure 2. The superluminal FXW. Shown is dependence (a) of the
real part and (b) of the modulus of the wavefunction on the
longitudinal and trans-verse coordinates. The modulus propagates
rig-idly from the left to the right along the axis z with a superluminal
speed [8,10].
Research Highlights • 59
Other localized waves are readily available via the Lorentz
transformation of the wave function given by Eq.(1) along the axis z.
One of such – the so-called focused X wave (FXW) is depicted in
Fig. 2. The strongly localized waist and the whole amplitude
distribution move rigidly and without any spread along the axis z
with a superluminal speed. It should be noted here that there is
nothing unphysical in the superluminality of the localized waves –
which is, moreover, an experimentally verified fact – since a superluminal group velocity does not mean as if information could be
transmitted faster than c [7]). For the FXW in the waist region (see
Fig. 2) the photon energy distribution has the same radial falloff as
was given by Eq. (2), while the axial localization follows a power law.
Hence, in its waist (cross-sectional) plane a one-photon (or
N-photon) field derived from the FXW possesses the same strong
localization at any time as the previously considered cylindrical field
does in any transversal plane any transversal plane at the instant t = 0.
Another localized wave derivable from Eq.(1) – the so-called focus
wave mode (see reviews [7,9] and references to the pioneering papers
of 1980.-ies therein) – leads to even stronger localization of the
photon energy. Namely, in this case the photon localization in the
waist plane turns out to be quadratically exponential (Gaussian
falloff):
| F( U o f, z W ) | 2 a U 6 exp( U 2 / la ) .
It could be argued that the well-known Gaussian beam pulse has the
same quadratically exponential radial profile in the waist region.
However, resorting to the family of the Gaussian beams (the GaussLaguerre and Gauss-Hermite beams, etc.) is irrelevant here. The
reason is that all these beams are solutions of the wave equation only
in the paraxial approximation not valid in the case of any significant
localization of wide-band (pulsed) superpositions of the beams,
whereas in fact, e.g., an exact solution corresponding to a lowestorder (axisymmetric) Gaussian beam has a weak power-law radial
falloff in the waist region [11].
60 • Biannual Report 2004/2005
In conclusion, we have shown that for certain cylindrical N-photon
states (N = 1,2,…) the localization in lateral directions breaks not
only the restrictions known from the textbooks but also that
established in Ref. [5] for the case of uniform spherical photon wave
functions. Our new results hold not only for photons but for number
states of any particles and throw new light on the localization of the
quantum fields.
REFERENCES
1. L. D. Landau and R. Peierls, Z. Phys. 62, 188 (1930).
2. I. Bialynicki-Birula, Photon wave function, in: E. Wolf (Ed.), Progress in
Optics, vol. 36, North-Holland, Amsterdam, 1996.
3. A. L. Akhiezer and V. B. Berestetskii, Quantum electrodynamics,
Interscience, New York, 1965.
4. L. Mandel and E. Wolf, Optical Coherence and Quantum Optics,
Cambridge University Press, Cambridge, 1995.
5. I. Bialynicki-Birula, Phys. Rev. Lett. 80, 5247 (1998).
6. P. Saari, M Menert, and H. Valtna, Opt. Commun. 246, 445 (2005).
7. P. Saari and K. Reivelt, Phys. Rev. Lett. 79, 4135 (1997).
8. P. Saari and K. Reivelt, Phys. Rev. E 69, 036612 (2004).
9. K. Reivelt and P. Saari, in: arXiv, physics/0309079.
10. H.Valtna, K.Reivelt and P.Saari, J. Opt. A: Pure Appl. Opt., 8,. 118
(2006).
11. P. Saari, Opt. Express 8, 590 (2001).
Multiphoton processes in intense laser fields
Viktor Peet
In recent years, interesting and unusual features of the so-called
nondiffractive or propagation-invariant light beams have attracted
considerable interest in applications of such beams in nonlinear
optics. In most cases the simplest coherent conical beams like Bessel
Research Highlights • 61
beams were used, but much less is known about nonlinear optical
processes driven by incoherent conical beams. Recently several
evidences have been found that conical excitation geometry allows
one to preserve a relatively high efficiency of a nonlinear process even
for laser beams with significantly degraded beam quality. Such a
tolerance may be very interesting and useful feature of conical beams
in the excitation of nonlinear optical processes and frequency
conversion of laser emission.
Resonance-enhanced four-wave mixing and generation of sumfrequency field in xenon have been studied under two-color excitation
by spatially coherent and incoherent conical laser beams. Comparisons of analogous results with a two-color excitation in an ordinary
geometry of focussed beams and in one-color Bessel beams have been
made. It has been shown that with incoherent laser beams the fourwave mixing process is much less degraded in conical excitation
geometry where an efficient generation of sum-frequency field can be
obtained despite of multiple wave-front aberrations. Such a tolerance
of conical beams results from their specific structure of coherent focal
domains that are extended significantly along the beam axis. It
preserves a relatively high degree of coherence for excitation processes
even for input beams with poor spatial coherence. Numerical simulation of sum-frequency excitation profiles for one- and two-color
conical beams has been carried out and good agreement with experimental observations has been obtained.
REFERENCE
V. Peet and S. Shchemeljov, Sum-frequency generation and multiphoton
ionization in spatially incoherent conical laser beams, Optics Commun.
246, pp. 451–463, 2005.
62 • Biannual Report 2004/2005
Decay of Anion and Cation Excitons into Frenkel Pairs
and Defect Triplets in LiF Single Crystals
Aleksandr Lushchik
For a long time, wide-gap LiF crystals (Eg # 14.2 eV) have been used
as optical materials and tissue-equivalent dosimetric materials. In LiF,
the creation energy of anion and cation excitons equals Ea # 13.1 [1]
and Ec # 62 eV [2], respectively. However, the processes of anion or
cation exciton decay into elementary radiation defects is studied
insufficiently. In 2004–2005 we performed a complex study of these
processes using the methods of VUV spectroscopy (photon energy up
to 70 eV) and thermoactivation spectroscopy in a temperature range
of 4.2–750 K [1,3–6]. Low-temperature decay of anion excitons with
the formation of Frenkel pairs (F-H pairs) has been thoroughly
studied and compared with that in earlier investigated KCl and KBr
crystals. The decay of a cation exciton into an anion one and several
electron-hole (e-h) pairs has been revealed as well. In the latter case
spatially correlated electronic excitations can be transformed into a
defect triplet, which is stable at 4.2–11 K and undergoes destruction
by a heating up to 16 K.
Fig. 1 shows the reflection spectrum and the excitation spectra for
the 3.4 and 4.2 eV emissions measured for a LiF crystal at 9 K. The
growth procedure of this highly pure crystal is described in [3]. The
3.4 eV emission of self-trapped excitons (STEs) is efficiently excited
at the direct formation of anion excitons by the photons of
hQex = 12.4–14.0 eV as well as in the region of band-to-band
transitions (hQex > Eg). A narrow excitation band at 12.2 eV can be
also detected in the excitation spectrum for 4.2 eV emission. The
4.2 eV emission is excited neither at hQexc < 11.8 eV nor in the whole
region of fundamental bulk absorption, that is untypical of impurity
or defect-related emissions in LiF. According to theoretical calculations [7], the absorption of the excitons at a clear and flat (100)
Research Highlights • 63
surface of LiF is peaked at 12.3 eV. The inset shows normalized
emission spectra measured for LiF at the photoexcitation selectively
forming bulk anion excitons or e-h pairs (13 and 16.2 eV photons,
respectively). The impurity/defect emission in the region of
4.5–5.9 eV (see inset) is excited by photons of 10 to 11.8 eV as well
as in the region of hQex > Eg. It should be mentioned that the emission
and excitation spectra change drastically in a LiF sample preirradiated at 295 K by krypton swift heavy ions (820 MeV,
5u1011 Kr/cm2) using the linear accelerator UNILAC of the GSI,
Darmstadt. The efficiency of the emission connected with the localized surface excitons is sharply reduced in the region of 12.2 eV in the
case of distorted crystal surface.
Figs. 2a and 2b present the curves of thermally stimulated
luminescence (TSL) in the region of 5–200 K measured for a LiF
crystal irradiated by electrons at 6 K. The analysis of the data
obtained by several experimental methods allowed to conclude that
the TSL peaks at 28–30 K are connected with the annealing of
I centres (F– interstitial ions), while the peaks at 38–40 and 50–60 K
are caused by the reorientation and hopping migration of H centres,
respectively. At 50–60 K a mobile H interstitial recombines with a
two-electron Fc centre and a released conduction electron subsequently participates in the radiative recombination with a localized
hole. A similar process occurs at 100–115 K, when an H interstitial
gets free from an impurity trap (even in a pure LiF some cations are
replaced by Na+ ions). The obtained TSL data as well as additional
direct measurements of temperature dependence of the radiationinduced absorption spectra and literature data on EPR and ENDOR
of H and HA centres confirm the decay of an anion STE into an F-H
pair in the LiF crystal. According to Figs. 2b and 2c, H and HA
interstitials are created at the direct optical formation of anion
excitons by 13.8 eV photons or at the recombination of electrons
with self-trapped holes (VK centres, hQexc = 17 eV). The efficiency of
F-H pair creation by VUV radiation at 4–8 K is low. In many alkali
64 • Biannual Report 2004/2005
halides dihalide H interstitials are oriented along closely-packed
<110> anion rows and a low-temperature crowdion mechanism of
interdefect separation inside F-H pairs provides defect stabilization
(see [4] and references therein). However, such crowdion mechanism
in LiF and NaCl is impossible because of the orientation of H centres
along <111> and a considerable spatial separation of F and H centres,
formed at a STE decay, is impeded. The efficient removal of an
H centre from an F centre becomes possible at T > 50 K due to a
hopping diffusion of H centres. At a slightly higher temperature
(T > 60 K) the mobile H centres interact with VK centres resulting in
the formation of F3– molecules (an absorption band at 11 eV) stable
in LiF up to a500 K [3].
Several TSL peaks were detected in a LiF crystal irradiated at 8 K
by 62 eV photons selectively creating cation excitons (see Fig. 2c): the
110 K peak is connected with the decay of HA centres, TSL at
130–140 K is accompanied by the annealing of the EPR signal of VK
centres, the thermal ionisation of Fc centres takes place at 155–160 K.
The Fc-TSL peak can be also registered after the direct optical
formation of anion excitons.
Of particular interest is the origin of the intense 13 K TSL peak in
irradiated LiF crystals (see [1,3,6]). The intensity of this peak is
especially high after the irradiation of LiF by X-rays (30–50 keV) or
1.5–30 keV electrons, while the 13 K TSL peak cannot be induced
after selective photoexcitation forming anion excitons (hQexc = 12.5–
14 eV) or separated electrons and holes (hQexc = 17 eV). In our
opinion, the creation of a group of spatially correlated electronic
excitations by a VUV exciting photon is needed for the appearance of
the 13 K peak.
In KBr and KCl, such excitation group can be created by an
exciting photon whose energy is sufficient for the formation of a
valence hole and a hot conduction electron. The hole undergoes selftrapping, while the electron creates a secondary anion exciton decaying into an F-H pair nearby a self-trapped hole. The subsequent
Figure 1. The reflection spectrum () and the excitation spectra of
3.4 (xx) and 4.2 eV emission () for a LiF crystal at 9 K. The
spectra were measured for a time-integrated (TI), fast (f, a time
window of 't = 8 + 26 ns) and slow component (s, 't = 52 + 148 ns).
A vertical arrow indicates the calculated energy of surface excitons [7].
The inset shows emission spectra at the crystal excitation by 13 eV (1)
and 16.2 eV photons (2) at 9 K.
Figure 2. The thermal annealing of the decay products of anion and
cation excitons in a LiF crystal irradiated at 6–8 K.
The annealing of the EPR signal of VK centres (1). The TSL curves
measured for 3.4 eV (2), 4.6 eV (3), 5.4 eV emissions (4) or an
integral signal (5–7) at the heating (E = 10 K/s) of the sample
irradiated by 13.8 eV (5), 17 (6) and 62 eV photons (7), 30 keV
electrons (2, 2c, 2cc, 4) or X-rays (50 keV, curve 1).
Research Highlights • 65
trapping of an electron by an H centre results in the formation of an
F-I-VK defect triplet (see, e.g., [8]).
The 13 K TSL peak can be formed after the irradiation of LiF at
8 K by 62 eV photons selectively creating cation excitons [6]. The
energy of 2–30 keV electrons is insufficient for the realization of the
knock-out (impact) mechanism of defect creation – even the lightest
of possible impurity ions (hydrogen) cannot be removed from lattice
sites by such electrons. Doping of LiF with Na+ or Mg2+ ions with the
concentration higher than 100 ppm leads to a significant decrease of
the intensity of the 13 K TSL peak [1,6]. This peak can be also
suppressed by additional stimulation of the irradiated sample at 8 K
by the photons causing photoionization of Fc centres. Such
Fc-illumination simultaneously leads to the appearance of a rapidly
dumping out with time photostimulated luminescence (PSL) at 5.7,
3.4 and 2.9 eV. Fig. 2a shows the TSL curves measured for 5.4 and
3.4 emissions connected with the direct or stepwise tunnel recombination of either of two electrons from an Fc with a VK centre. According to Fig. 2a, the ~13 K TSL peak has a complex structure. A lowtemperature component is efficiently detected for 5.4 eV emission
caused by the direct tunnel recombination of an electron from an Fc
centre with a VK centre. The emission of STEs (3.4 eV) arises due to
the tunnelling of an electron from an F or Fc centre to a VK via an
excited triplet exciton state. Fig. 2a demonstrates two components of
TSL at ~13 K measured for 3.4 r 0.1 eV emission (curves 2c and 2cc).
The analysis of the above-mentioned results allowed us to
conclude that the cation exciton in LiF decays into an anion exciton
(~13 eV), while the rest of the energy (~49 eV), after intermediate
processes connected with the formation of a photon or an Auger
electron, is expended by creating up to three e-h pairs. A shortwavelength analogue of the Raman effect, when excitons act as
phonons at the scattering of X-rays, was theoretically considered by
Agranovich and Ginzburg back in 1961 [9]. Previously we
experimentally revealed (see, e.g., [4]) the decay of a cation exciton
66 • Biannual Report 2004/2005
(Ec # 34 V) into one anion exciton (Ea # 8 V) and two e-h pairs in
NaCl crystals. According to Kamada et al. [10], the ejection efficiency
of lithium atoms in an excited state from LiF is practically equal in
magnitude for the cases of crystal irradiation by 13 eV or 62 eV
photons. The latter result confirms the decay of a cation exciton with
the formation of an anion one. This free anion exciton undergoes
self-trapping with the subsequent decay into an F-H pair.
The decay of a cation exciton in LiF at 8 K causes the formation
of an F-H pair, spatially separated by several interion distances a VK
centre and a conduction electron. This group of electronic excitations
transforms mainly into a triplet of spatially correlated defects –
Fc-H-VK. A further detail study of the decay of cation excitons with
the formation on anion ones in radiation-resistant materials (e.g.,
MgO), where the formation energy of a Frenkel pair exceeds the
value of Eg, lies ahead.
This work has been done in collaboration by V. Babin,
E. Feldbach, M. Kirm, A. Kotlov, T. Kärner, I. Kudryavtseva,
P. Liblik, A. Lushchik, Ch. Lushchik, S. Nakonechnyi, V. Nagirnyi,
E. Vasil’chenko (IPUT) and L. Pung (Physics Department, Tartu
University).
REFERENCES
1. S. Nakonechnyi, T. Kärner, A. Lushchik, Ch. Lushchik, V. Babin,
E. Feldbach, I. Kudryavtseva, P. Liblik, L. Pung, E. Vasil’chenko,
J. Phys.: Condens. Matter 18, 379 (2006).
2. A. M.-E. Saar, A. A. Maiste, M. A. Elango, Sov. Phys. Solid State 15,
1663 (1974).
3. E. Vasil’chenko, I. Kudryavtseva, A. Lushchik, Ch. Lushchik, V. Nagirnyi, Phys. Status Solidi c 2, 405 (2005).
4. M. Kirm, A. Lushchik, Ch. Lushchik, Phys. Status Solidi a, 202, 213
(2005).
Research Highlights • 67
5. A. Lushchik, A. Kotlov, Ch. Lushchik, V. Nagirnyi, K. Schwartz,
6.
7.
8.
9.
10.
E. Vasilçhenko, In: HASYLAB Activity Report 2005, Part I, DESY,
Hamburg, Germany, p. 257.
A. Lushchik, Ch. Lushchik, M. Kirm, V. Nagirnyi, F. Savikhin,
E. Vasil’chenko, Nucl. Instr. and Meth. B (2006) accepted.
N.-P. Wang, M. Rohlfing, P. Krüger, J. Pollmann, Phys. Rev. B 67,
115111 (2003).
M. Kirm, A. Lushchik, Ch. Lushchik, I. Martinson, V. Nagirnyi,
E. Vasil’chenko, J. Phys.: Condens. Matter 10, 3509 (1998).
V. M. Agranovich, V. L. Ginzburg, Sov. Phys. JETP 13, 683 (1961).
M. Kamada, N. Takahashi, S. Hirose, 1999 J. Electron Spectrosc.
Relat. Phenom. 101–103, 599 (1999).
Resonant Inelastic X-ray Scattering at the F 1s
photoabsorption edge in LiF
1
1
Arvo Kikas,1 Tanel Käämbre,
Agu Saar,1 Kuno Kooser,
Ergo
1
2
Nõmmiste, and Indrek Martinson
1
Institute of Physics, University of Tartu, Riia 142, EE-51014 Tartu, Estonia
2
Department of Atomic Spectroscopy, Lund University, Professorsgatan 1,
S-22100, Lund, Sweden
Resonant inelastic X-ray scattering spectroscopy (RIXS) has in recent
years attracted attention as a source capable providing a unique
variety of information about the electronic structure of solids. For
example, it has been shown to be a particularly useful technique when
investigating the structure of the valence and conduction band
electronic structure in high-symmetry carbon compounds and the
charge transfer induced processes in transition metal compounds.
Here we present the results of a study of threshold processes at the
F 1s photoabsorption edge by RIXS. Solid LiF is an ionic compound,
in which the chemical bond is constituted by the electrostatic forces
between the Li+ and the F– ions. The F1s photoabsorption spectrum
68 • Biannual Report 2004/2005
of LiF has a wide threshold peak, whereas generally in ionic solids the
sharp excitonic pre-threshold peaks tend to dominate. However, it
has recently been shown that the photoabsorption spectrum of LiF
cannot be calculated without taking the electron-core hole interaction
into account [1]. Experimentally, the spectral features, which stem
from a core exciton have been identified in the resonant Auger spectra
[2] and in the non-resonant inelastic X-ray scattering spectra [3].
The experiments described in this report were performed at the
“bulk” branch of beamline I511. Typical resolutions used were
0.3 eV (100 µm exit slit) for the SX700 monochromator at the
beamline and 0.3 eV for the Rowland circle mounted X-ray emission
spectrometer on the endstation. The sample was a LiF single crystal.
The incidence angle of the incoming light was set to 60 degrees.
Figure 1 gives an overview of the measured X-ray emission spectra
for the excitations in the vicinity of the F 1s photoabsorption
threshold. The top curve in Figure 1 displays a fluorescence spectrum
at non-resonant excitation. The fluorine K X-ray emission peak is
seen at 677.8 eV. This emission is due to transition, where electron
from valence band fills inner shell hole (see energy scheme at Fig. 2).
In the 681–682 eV energy range, a satellite peak appears, which
originates from an initial state containing an additional vacancy in the
valence band. These satellites appear for excitation energies above
approximately 720 eV.
It can be seen that the spectra, measured at low excitation energies,
consist of two different kinds of structures. One of these remains at
constant emission energy (677.8 eV) which coincides with the F K
characteristic X-ray emission line. The other one is a wide band
which shifts to higher energies together with the excitation energy at
approximately constant energy loss. The latter thus behaves in a
manner characteristic of the radiative (Raman) inelastic X-ray
scattering. At the photoabsorption threshold this structure merges
into the K characteristic emission line. Note that the half width of
this merged peak changes significantly at the threshold. The presence
Research Highlights • 69
of the K fluorescence peak in pre-threshold spectra refers to the
circumstance, that at these photon energies the photons from the tail
of the incoming photon energy distribution excite the characteristic
K fluorescence.
In order to better understand these spectra we performed a simple
simulation based on the Kramers-Heisenberg formula. Two different
calculations have been performed. A strict approach has presented in
Ref [4]. Here we present a simpler model, which bases on the
approach, previously used for the resonant Auger spectra of Ag and
Cu metals [4, 6]. By the resonant scattering theory, the energy
distribution I (!Z in , !Z out ) of the outcoming photons !Z out for the
excitation energy !Z in can be written in the following way:
I (!Z in , !Z out )
U (e) N ph (!Z in !Z )ded!Z
2
2
2
2
>
@>
@
0 0 (!Z e E K ) *K / 4 (!Z e !Z out E L ) *L / 4
ff
C³ ³
where U is the density of final states, N ph is the experimental
photon energy distribution, *K and *L are lifetime widths of the
corresponding levels, E K and E L are binding energies of the
corresponding levels, C is the scale factor, which includes matrix
elements.
In this simulation we take into account the scattering on the
bound (excitonic) and the free (conduction band) states. For this we
approximate the conduction states with a step function while an
additional Gaussian function at 1.25 eV below the onset of the
conduction states is taken as an approximate description of the
excitonic states (see Fig. 2). The energy distribution of the incoming
photons has been approximated as a sum of Gaussian and Lorentzian
functions with the intensity ratio of 4:1. Such shape of the latter
distribution is crucial for the agreement with the pre-threshold
spectra, because without the Lorentzian component the simulation
does not reproduce the emission intensity at 677.8 eV for the prethreshold excitation. The results of this simulation are presented in
70 • Biannual Report 2004/2005
Figure 3. It is seen that the form of the experimental spectra is
reproduced, as well as the measured changes in the peak widths.
Note, that in calculated spectra (a) and (b) there is a peak between the
scattered peak and characteristic K fluorescence, which is barely seen
in experimental spectra. This peak is a result of scattering on the
excitonic state and it merges into the K fluorescence peak in
spectrum (c), causing the shift and broadening of the resulting peak.
Similarly in spectrum (e) the shift and broadening of the emission
peak is result of merging of the K fluorescence peak with the peak
originating from the scattering on conduction states. However, the
simulated spectra are somewhat narrower than the experimental. The
reason for this are probably that the phonon broadening is not taken
into account in the simulation. Neither does the simulation reproduce the low energy shoulder in the emission spectra. This may be
due to the circumstance that the density of valence states is not taken
into account in simulation. Note, that this simple approach gives a
result, which agrees well with the more strict approach of Ref. [4].
We note that the particular amount of the ‘Lorentzian contribution’, simulating the extended energy tail(s) of the monochromator
function, should firstly be seen as an aberration from the fully
Gaussian energy distribution in the transmission of an ideal monochromator – thus the particular amount of the Lorentz contribution
depends on the particular physical machine that is used and the
parameters therein. The non-negligible contributions from higher
diffraction order light from the monochromator can be out-ruled in
this experiment, since placing the monochromator energy approximately 100 eV below the F 1s excitation threshold resulted in nondetectable (i.e., below the noise level) F K emission from the sample.
It is interesting to note, that the RIXS spectra at F 1s edge in LiF
differ from the case of O 1s edge MgO, because an additional
narrowing of the X-ray fluorescence peak was not observed in MgO,
which can be related to the absence creation of a core exciton in the
case of sub-threshold excitation in MgO [7].
PFY
TEY
d
g
c
f
b
a
h
e
690
695
700
705
hQin [eV]
n
h
g
f
e
d
c
b
a
665
670
675
680
685
X-ray emission energy [eV]
Figure 1. The scattering spectra recorded at excitation energies (see
inset) in the fluorine 1 s absorption resonance range. Inset: the 1s
photoabsorption profile of LiF showing the excitation energies for the
RIXS spectra. The excitation energy for spectrum n is 732 eV.
Figure 2. Scheme of transitions for resonantly excited F K X-ray
fluorescence in LiF.
Excitonic
Continuum
Total
g
f
e
d
c
b
a
672
674
676
678
X-ray emission energy [eV]
Figure 3. The calculated RIXS profiles, corresponding to the
excitation energies used in the experiment (see Fig. 1).
Research Highlights • 71
Our RIXS spectra allow to identify a single core exciton in LiF,
similar to the results obtained using non-resonant X-ray scattering
[3]. On the other hand, core excitons were detected in resonant Auger
spectra at excitation energies 690.5 and 691.7 eV [2]. This
controversy can be solved by assuming that the higher energy core
exciton state, which is observed in RAS, is a result of the postcollision induced recapture of a slow photoelectron. This mechanism
has been previously discussed in the case of Na 1s excitations in NaF
[8]: right above the 1s ionization limit, the outgoing photoelectron can
be recaptured into bound state by post-collisional interaction with a
fast Auger electron. As a result, in the resonant KLL Auger decay
spectra a new peak appears, which is shifted to higher kinetic energies
as compared to the normal Auger peak. Because such an interaction is
not possible in the case of radiative decay, we do not observe the
corresponding exciton in the radiative decay spectra, and so it cannot
either be seen in the non-resonant X-ray scattering spectra of LiF.
REFERENCES
1. Eric L. Shirley, Phys. Rev. Lett. 80 (1998) 794–797.
2. H. Aksela, E. Kukk, S. Aksela, A. Kikas, E. Nõmmiste, A. Ausmees,
M. Elango, Phys. Rev. B, 49 (1994) 3116.
3. K. Hämäläinen, S. Galambosi, J. A. Soininen, E. L. Shirley, J.-P. Rueff,
and A. Shukla, Phys. Rev. B, 65 (2002) 155111.
4. A. Kikas, T. Käämbre, A. Saar, K. Kooser, E. Nõmmiste, I. Martinson,
V. Kimberg, S. Polyutov, and F. Gel’mukhanov, Phys. Rev. B, 70,
085102 (2004).
5. W. Drube, R. Treusch, and G. Materlik, Phys. Rev. Lett., 74 (1995) 42.
6. A. Föhlisch, O. Karis, M. Weinelt, J. Hasselström, A. Nilsson, and
N. Mårtensson, Phys. Rev. Lett., 88 (2002) 027601.
7. A. Kikas, T. Käämbre, V. Kisand, A. Saar, K. Kooser, E. Nõmmiste, I.
Martinson, J. Electron Spectrosc. and Relat. Phenom, 144–147 (2005),
845.
8. A. Kikas, E. Nõmmiste, R. Ruus, A. Saar, I. Martinson, Phys. Rev. B, 64
(2001) 235120.
4. SCIENTIFIC REPORT
Laser spectroscopy and applications
of photosensitive materials
The main directions of the reasearch were high resolution spectroscopy (including single molecule spectroscopy and spectral hole
burning) of solid phases (glasses, incommensurate systems), synthesis
and spectroscopy of layered structures, modelling of dynamics of biomolecular structures, search of applications for the materials and
phenomena under consideration. The reference number are those of
the list of Section “Publications”.
Spectroscopy and applications of metal oxide
films doped with rare earth ions
J. Aarik, V. Kiisk, S. Lange, H. Mändar, I. Sildos
A novel method of preparation of optical films was developed, based
on growth of metal oxide (TiO2; ZrO2, HfO2) nanolayers of controlled thickness by atomic layer deposition or sol-gel technique. ALD
films were doped with luminescent rear-earth ions (Sm3+, Eu3+, Tb3+)
by ionic implantation, sol-gel materials were doped by adding respective salt to the educt compounds. The materials obtained were
characterized by x-ray diffraction and Raman scattering, the surface of
the films was studied with nanoresolution using an atomic force
microscope. It was shown, that the doping reduces the size of
nanocrystallites. Luminescent characteristics of the materials were
Scientific Report • 73
studied using for excitation both UV lasers (193, 248, 355 nm) and
synchrotron radiation in VUV in Hamburg. Due to good spectral
and temporal characteristics of excitonic self-emission of ZrO2 and
HfO2 (UV, decay times of nanoseconds) these materials have
prospective applications as soft x-ray scintillators. It was shown, that
UV absorption in the fundamental absorption band of these materials
is accompanied by an efficient energy transfer, resulting in excitation
of the rare-earth impurity ions and leading to characteristic
luminescence of these ions. By using a saturation technique an effective cross-section of 10 –15 cm2 for this excitation channel was estimated. It was shown that novel luminescent materials can be
developed based on the systems studied. In Sm3+-doped TiO2 films
sensitivity of the impurity emssion to the oxygen content in the
surrounding gas was found, promising applications in sensorics.
Usage of Sm3+:TiO2 layers as waveguides for optical emission was
demonstrated. Dependence of the exciton as well as impurity luminescence in a thin anatase (TiO2) film on the waveguide characteristics (thickness, substrate material) was studied and modelled. The
structure of the waveguide determines formation of specific spectral
peaks and polarizational characteristics in the leak modes of the layer.
In the spectra of nitrogen-doped diamonds an experimental
evidence was found for theoretical results (V. Hizhnjakov, H. Kaasik)
on peculiarites of the phase relaxation in impurity ions in a situation
of dynamical instability.
As a main instrumental development implementation of a confocal Raman-fluorescence microscope should be mentioned, yielding
lateral and axial resolutions of 3,3 Pm and 14 Pm, respectively. Its
operational parameters were tested by measurement of the distribution of nickel-nitrogen (NE8) impurity centres in a diamond
crystal. Such defects were shown to be located in a surface layer of
200 Pm thickness due to their formation in an annealing process.
[22, 27, 41, 155, 159, 220]
74 • Biannual Report 2004/2005
Laser probing of critical phenomena and single-molecule
dynamics in incommensurate biphenyl
An. Kuznetsov, A. Laisaar, V. Palm, M. Pärs, A. Suisalu
By reducing the critical temperature of a structural phase transition
with application of hydrostatic pressure an anomalous behavior of
pyrene dopant spectra in incommensurate biphenyl was observed.
The photoluminescence spectra of pyrene dopant were studied for
temperatures of 4.7–40 K at pressures of 0.2–2.0 kbar. Temperature
dependence of a dublet splitting of the pyrene 597 nm emission line
was observed in the first incommensurate phase. From these data the
pressure dependence of the phase transtion temperature between the
commensurate and the first incommensuret phase was established.
Interesting results were obtained for the low-temperature region of
quantum fluctuations (T < 10 K), where the phase transtion pressure
(Pc ~1,8 kbar) is practically independent on temperature. In this
region (from 4.7 to 10 K) an anomalous contraction of spectral line
was observed with increasing tempearture, converting further (for
(10–40 K) to a “normal” temperature broadening. [63]
Novel samples for single molecule spectroscopy – thin (of several
microns thickness) pyrene-doped monocrystals of biphenyl – were
grown by cosublimation at 180o C in an inert gas environment. The
samples exhibit terrylene single-molecule lines of intensity exceeding
by an order of magnitude those in polycrystalline samples. As a result,
a better temporal resolution for recording the spectra was reached,
used to measure fast processes of spectral diffusion in cooperation
with the University of Lund. [48]
Scientific Report • 75
Temperature and pressure effects on impurity spectra in
glasses and mixed crystals
J. Kikas, An. Kuznetsov, A. Laisaar, I. Renge, A. Suisalu, U. Visk
Results on pressure reduction of the residual hole broadening in
temperature cycling experiments in a polymeric (polystyrene) glass
were interpreted within a common theoretical frame, developed
earlier for isothermal hole burning. A key ingredient in the interpretation is an assumption about asymmetric distribution of the
asymmetry parameter in the soft potential model for excitations in
low-temperature glasses (collaboration with V. Hizhnyakov).
In a Sm2+-doped Na-borate glass (33 Na2O – 66 B2O3) an
anomalous linear temperature dependence of the homogeneous
spectral width of impurity 7F0 l 5D0 electronic transition was
observed and interpreted. The homogeneous width was measured by
spectral hole burning and fluorescence narrowing techniques for
temperatures 5 293 K at normal pressure and for temperatures 5, 80
and 120 K at various pressures up to 8 kbar. The observed at
T > 20 K linear (v T) temperature dependence was interpreted by a
modulation broadening of the electronic transition by low-frequency
localized vibrational modes. In the Na-boron glass such a mechanism
prevails over the standard two-phonon process of dephasing. Under
the applied hydrostatic pressure the inhomogeneous 7F0 l 5D0
transition band at 684 nm in the above systems shifts to longer
wavelengths. Surprisingly, such a shift is larger at 77 K compared to
the room temperature value (0.066 vs 0.041 nm/kbar, respectively).
Unusual observation is also a temperature narrowing of the
inhomogeneous band (4.4 nm at RT, compared to a value of 5.4 nm
at 77 K). The established absence of an observable pressure narrowing
of homeogenous spectral lines in the borate glass calls for an extension
of the existing theoretical models (cooperation with the University of
Erlangen-Nuremberg).
76 • Biannual Report 2004/2005
A detailed study of pressure dependence of Sm2+ dopant photoemission spectra in Ba12F19Cl5–xBrx : Sm2+ (x ~ 1) mixed crystal up to
7 kbar was carried out for 80 and 121 K, revealing a pressure-induced
narrowing of the inhomogeneous spectral band (collaboration with
R. Jaaniso).
Possibilities to determine and predict homogeneous and inhomogeneous characteristics of dopant spectra as functions of temperature
(up to 300 K) and pressure were analysed, including situations where
the 0–0 line is spectrally not resolved. As a starting point for extrapolations low-temperature (5–50 K) and low-pressure (up to 200 bar)
characteristics of spectral holes in solvent glasses and polymers were
used. The temperature-induced narrowing of the site energy distribution due to the thermal expansion of matrix was pointed to as a
counterbalancing factor to the temperature-induced broadening of
spectra. Qualitative features of the effects were described in a simple
model using Lennard-Jones potentials. [53,158, 201]
Quantum chemical modelling of fluorescence and
conformational dynamics of BFP
K. Mauring, V. Krasnenko
Using quantum-chemical calculations differences of the excited state
lifetime in two conformations of the blue fluorescent protein (BFP)
were attributed to formation of hydrogen bonds. From the experimental results on influence of temperature and pressure on the
intensity of fluorescence and on the excited state lifetime, two different conformation of BFP were shown to exist, distinguished by
existence or absence of hydrogen bonds between the chromophore
and adjacent amino acids. At decreasing temperature or increasing
pressure the ratio of the hydrogen-bonded conformations increases,
resulting in an increase of the fluorescence intensity and of the exited
state lifetime. The question, why the fluorescence from the non-bon-
Scientific Report • 77
ded conformation is strongly quenched, was answered by quantumchemical calculations. Upon absorption of a light quantum, the
chromophore is transferred to a quite unstable excited state, where the
forces induced by redistribution of the electron density try to deform
it. As a result, the adiabatic energy surfaces of the ground and excited
state approach each other (or even intersect), quenching the fluorescence. The hydrogen bonds, however, make the chromophore
more rigid and reduce the twist deformation, increasing thus the yield
of fluorescence. Prospects for using this effect for sensing temperature
and pressure were analysed. [186]
Spectral sensing and environmental analysis
A. Suisalu, K. Rebane, M. Kleemann, J. Kikas
A moisture-sensitive polymer membrane was developed and characterized, based on polymethyl-metacrylate (PMMA) film doped with
solvatochromic Reichardt’s betaine dye. The sensing effect stems from
a hyperchromic effect and a hypsochromic shift of the absorption
spectra. It was shown that a common model of dual gas sorption
applies to the dynamics of water molecules in the glassy PMMA.
A method was implemented for a highly sensitive fluorescent
analysis of cancerogenes and other compounds in water, including
sample extraction, processing and spectroscopic measurements in
frozen n-alkanes (Shpolskii matrices), aiming at a sensitivity level of
single-molecule detection. [246]
Compiled by Jaak Kikas
78 • Biannual Report 2004/2005
Nanostructured materials
This project centers on the application of atomic-layer-deposition,
pulsed-laser-deposition, and sol-gel methods for the nanodesign of
solids. Different coatings, insulator materials, materials for gas
sensing, fibers, etc. are studied, nanoscale measurement techniques
advanced, and theoretical approaches worked out. Two years’ results
of the five research groups involved are as follows.
For the group including J. Aarik (leader), A. Aidla, J. Asari, A. Gerst,
A.-A. Kiisler, H. Koppel , M. Lulla, R. Lurich, A. Niilisk, R. Pärna,
R. Rammula, P. Ritslaid, A. Rosental, V. Sammelselg (Institute of
Physical Chemistry), A. Tarre, and T. Uustare:
HfO2 films, atomic layer deposited on Si substrates were compared. It
was shown that at temperatures above 450°C the growth from
HfCl4–H2O starts in an inhibited way, in the form of threedimensional islands. Since the thickness of 2–3 nm, the films contained a cubic HfO2 crystal phase. The initial growth turned faster
and more two-dimensional when a 1–2-nm-thick buffer layer
deposited at 300 °C was used. Upon transfer to the HfI4–H2O or
HfI4–O2 precursor pairs, considerably more homogeneous ultrathin
films were obtained. Along with the improvement in the homogeneity of the films, there was a decrease in the ratio of the crystal
phase to the amorphous phase ratio in the films and an improvement
in the film smoothness. At temperatures 180–300 °C, the growth
turned sufficiently fast and steady already at thicknesses below 1 nm.
It was shown that, in the beginning, the growth of HfO2 films on Si
substrates covered with Pt, Ir, and Ru layers was substantially less
inhibited than that on the pure or chemical-oxide-covered Si
substrates. Also, the stationary growth rate was then higher and the
creation of the crystal phase faster.
In our atomic layer grown HfO2–Si, Al2O3–Si, and TiO2–Mo
structures interesting from a point of view of microelectronics, almost
Scientific Report • 79
always a transition layer of up to 3 nm was revealed between the
substrate and the film. The layer consisted of a mixture of the oxide
that was deposited and the oxide of the substrate material (Si or Mo).
In the case of HfO2, it was found that at temperature 225°C the
growth of the material started in the amorphous phase and the signs
of crystallization appeared only in the course of the growth. The
process continued so that the part with a crystallized cubic structure
grew faster than the amorphous part. In the films grown at 300°C, a
layer of less than 5 nm was amorphous and in the rest of the film, the
existence of the monoclinic phase was registered. The films, grown at
temperatures 350–750°C, contained the monoclinic phase all through
the film. Importantly, it turned out that the HfO2 films grown in the
range of 350–400°C did not have a transition layer of a mixed oxide.
It was ascertained that in the initial phases of the atomic layer
growth of ZrO2 (deposition temperature 500°C), there formed and
dominated the metastable tetragonal phase. Upon further growth, the
content of the phase stayed almost constant, but its proportion
decreased due to the addition of the stable monoclinic phase.
With the increase of the pressure and flow rate of the carrier gas
(N2), a slow-down of atomic layer deposition of ZrO2 and HfO2 films
was observed. The HfO2 films grown at a higher flow rate contained
more metastable phase and less chlorine, a residue from metal precursors (HfCl4 or ZrCl4). The surface of these films was smoother and
their refractive index higher. The effect of the carrier gas was
associated with the changes in the concentration of the metal-precursor and OH groups on the surface of a growing film.
When depositing gas sensitive SnO2 films on –Al2O3(0 1 2)
substrates from the precursor pair SnI4–H2O2, an acceptable atomic
layer growth rate was achieved in a temperature range of 100–600°C.
In the case of the precursor pair SnI4–O2, the respective range started
at 400°C. In both cases, the films had a stable tetragonal crystal
structure. At the deposition temperature of 750°C, in a narrow
thickness range SnO2 epitaxy was realized. In the growth experiments
80 • Biannual Report 2004/2005
from SnI4–O2 at temperatures 400–750°C, MgO(1 0 0), Pt/Si and
TiO2/Si substrates were also used. In the first case, only a weak
tendency of epitaxial growth was revealed. It was characterictic of the
second and third case that the increase of the thickness was accompanied by an increase in the size of crystallites. On Pt/Si substrates,
the growth of SnO2 films, in correlation with a high surface roughness, was exceptionally fast.
At atomic layer deposition of gas-sensitive Cr2O3 films, CrO2Cl2,
and CH3OH were chosen as precursors, and SiO2, Si(1 0 0), oxidized
Si, and –Al2O3(0 1 2) as substrates. The films grew at a satisfactory
rate when the temperature was relatively high (400–500°C). The
growth resulted in crystalline films with the eskolaite structure. The
growth on the sapphire substrates was epitaxial. Substitution of TiCl4
for CrO2Cl2 allowed also growing of TiO2 films in the abovementioned temperature range. Thus, a possible way of atomic layer
deposition of Cr2O3–TiO2 mixtures for resistive gas sensors was
paved.
For the group including R. Jaaniso (leader), T. Avarmaa, A. Floren,
M. Kodu, A. Kärkkänen, and I. Kärkkänen:
A model was constructed for describing luminescence quenching in
nonordered oxygen-sensitive solids, which takes into account the
inhomogeneous distribution of the natural and oxygen-induced
quenching rates. Model calculations were compared with the experimental quenching curves measured on PMMA films activated with
Pd-tetraphenylporphyrin. A positive correlation between the natural
and oxygen-induced quenching rates was found.
It was shown that the photostability of Pd-tetraphenylporphyrin
and Pd-tetrakis(pentafluorophenyl)porphyrin molecules in PMMA
depends on the fact whether oxygen is present or not. A lower photostability in the presence of oxygen was explained by the influence of
the singlet oxygen generated at the energy transfer. The study of the
stability of kinetic parameters demonstrated that while physical
Scientific Report • 81
ageing affects the effectiveness of energy transfer to oxygen through
the change in its diffusion rate, the photochemical ageing affects the
natural quenching time. A different character of photoproducts in the
case of the two molecules in view was determined.
Energy transfer in light emitting diode materials based on
poly(vinylcarbasol) activated with Pd-tetraphenylporphyrin was
studied. In luminescence kinetics, besides oxygen-induced quenching,
concentration quenching was revealed, when the mass percent of the
dye exceeded 1. The fact was explained by Förster energy transfer to
free porphyrin. To describe the experimental data, a distribution
function that takes into account the energy transfer to oxygen and
immobile acceptors was created. All above results on porphyrinactivated luminescence bear a relation to oxygen sensors based on
luminescence quenching. The sensor prototype was tested by
determining the oxygen consumption of butterfly pupae.
It was concluded from the measurements of the conductivity of
single-wall nanotube films illuminated in various gases and vacuum
that the decrease in the conductivity is due to oxygen photodesorption. The fast and reversible conductivity changes induced by
polar molecules were associated with physisorption on the surface of
nanotubes, while long-time photoprocesses (and the subsequent
reverse processes) were attributed to the adsorption on nanotube
defects or contact surfaces between the nanotubes. Comparison tests
in dry and humid argon and oxygen showed that water that was
photodesorbed and, subsequently, slowly adsorbed, is relatively
strongly bonded to nanotube films. The tests also pointed to the
interrelationship between oxygen and water sorption.
It was shown that by pulsed laser deposition it is possible to grow
Cr2O3–TiO2 films with a Ti content of 5–20 at.%. The films were
deposited onto Si substrates in the rare oxygen atmosphere. The films
crystallized when the O2 pressure exceeded 10–2 mbar and the
temperature was higher than 400–450°C. The advantageous size
(10–20 nm) of crystallites was achieved at temperatures 500–550°C.
82 • Biannual Report 2004/2005
In the case of 550°C films, the content of the crystal phase was
estimated to be 80%. It was found that in the thickness range of
10–30 nm, the film crystallinity did not depend on the thickness.
The crystallinity improved when the energy density of laser pulses was
decreased. Further improvement was achieved by growing or
annealing at temperatures above 600°C, but crystallites size exceeded
then 100 nm.
For the group including A. Lõhmus (leader), M. Järvekülg, I. Kink,
M. Lobjakas, R. Lõhmus, M. Paalo, V. Reedo, K. Saal, J. Šulga,
M. Timusk, T. Tätte, and S. Vlassov:
Elaboration of a prototype nanotomograph based on scanning probe
microscopy and pulsed laser etching was continued. An opportunity
to observe the scanning and etching area by means of a digital optical
microscope was added. The accuracy of horizontal movement was
improved to be on the micrometer level. The device was used for
studying the effect of laser irradiation on the surface of mica. It
turned out that it was only in the case of the smallest irradiance used
that the removal of material was sufficiently homogeneous.
It was shown that the tip radius of the transparent and electrically
conducting SnO2 probes prepared by sol–gel technique depends on
the fiber drawing velocity, humidity of the atmosphere, and viscosity
of the source material. The radius could be minimized to 15–25 nm.
The probes allowed one to collect the tunnel current generated light
and get surface images with a nanoresolution.
The properties of the nanostructured copper, obtained by the
method of strong plastic deformation, were studied after its
mechanical and thermal processing. A connection between size of the
granules (40–120 nm) and mechanical strength of the material was
revealed. With the increase of size, mechanical strength decreased and
yielding increased.
Methods of preparation of aminofunctional SiO2 films by sol–gel
technique were elaborated. The methods allow one to vary the surface
Scientific Report • 83
concentration of amino groups and the degree of film hydrophility.
Usability of the films as substrates for DNA microarray analysis was
experimentally proved. In further investigations, the optimal content
of 3-aminopropyltrimetoksysilan in the films, necessary for binding
DNA, was determined. The surface concentration of amino groups
was assessed.
Next, sol–gel syntheses of HfO2 in which hafnium tetrabutoxide
dissolved in butanol was polymerized by addition of H2O in the
presence of an HCl catalyst will be described. By sol–gel technique,
pure HfO2 films and the films doped with rare-earth metal ions
(Sm3+, Tb3+, Eu3+) were prepared. Dip coating was successively carried
out from prepolymerized 5% hafnium polymer solution in hexane.
For doping, SmCl3, TbCl3 or EuCl3 was added to the water necessary
for starting the polymerization. As a result, films with an even
distribution of impurities were created. Compared to the ion
implantation, the procedure is simpler and the scale of the applicable
impurities larger. The surface roughness of the films was in the range
of nanometers.
Methods for preparation of HfO2 fibers with a diameter of 10–50
µm were elaborated. It was shown that sol is most suitable for fiber
drawing if the concentration of the catalyst used is larger than 0.2%.
The tensile strength of the fibers was measured to be 170 MPa.
It was shown that by processing of hafnium polymer, microscopic
tubes or rods with dimensions about 1 u 100 µm can be precipitated.
The objects were oxidized at 600°C. The final products have a
potential for the use as probes in atomic force microscopes and nearfield scanning optical microscopes, catalysts with a large specific
surface area and sources for preparation of carbides.
Methods for preparation of microstructured HfO2 surfaces from
prepolymerized hafniumtetrabutoxide were worked out. The height
of the surface structures (pyramids) was measured to be 2–3 mm and
the width 3–10 cm. These surfaces can be used in detectors of
energetic particles.
84 • Biannual Report 2004/2005
For the group including P. Adamson and A. Kasikov:
Theoretical studies of light reflection from media consisting of
ultrathin dielectric biaxially anisotropic homogeneous films on
massive absorbing or transparent isotropic and homogeneous substrates were carried out. It was shown that if the film thickness d is
considerably smaller than the light wavelength and the substrate is
transparent, the contribution of each film to the reflectance is a
nonadditive second-order infinetisimal. In the case of absorbing substrates, the light intensity change caused by each film is proportional
to d/ .
The ellipsometry theory was developed for a system of several
arbitrary anisotropic nanolayers. Approximation equations for differential ellipsometric angles were derived. It was shown that in the case
considered, in addition to the traditional ellipsometric angles the socalled generalized ellipsometric angles can be used. Opportunities of
applying the approximation for the determination of parameters of
anisotropic stratified nanostructures from differential ellipsometric
measurements were analyzed.
Various models were used for determining the optical parameters
of depth-inhomogeneous vacuum evaporated ZrO2 films from
transmission spectra. Among envelope models, a model by Swanepoel
applied with a correction obtained in the region of smallest dispersion, turned out to be the best. It was shown that when describing
multiparameter inhomogeneity, the two-layer model has advantages
in comparison with the linear one.
Transmission spectra of atomic layer deposited TiO2 films were
analyzed using Lorentz dispersion and the two-layer model. It turned
out that the deposition parameters markedly influence the depth
dependence of the refractive index. The dependence was
demonstrated to be assessable even if the interference fringes are
weakly developed.
Scientific Report • 85
For the group including P. Konsin and B. Sorkin:
The free energy of oxide perovskites (BaTiO3, KNbO3, etc.) was
calculated taking into account the electron–lattice hybridization between the valence and conduction bands and the dependence on the
electron wave vector. The dependence of the permittivity of quantum
paraelectrics (SrTiO3, KTaO3, CaTiO3) on the electric field was
investigated. Its gigantic increase in SrTi16O3 when weak electric
fields and ultraviolet illumination are applied was predicted.
By analogy with the theory of superconductivity in graphite intercalation compounds, a model for the superconductivity in MgB2 was
proposed with all actual intraband and interband electron–lattice and
Coulomb interactions taken into account. The specific heat and
superconducting gaps were estimated.
On the basis of a two-component model, the superconductivity
transition temperature in function of the concentration of holes p in
La2–xSrxCuO4 films was calculated. The dependences of the Ginzburg–Landau coherence length and the upper critical magnetic field
on p for cuprates were shown to have a minimum and maximum,
respectively.
Compiled by Arnold Rosental
86 • Biannual Report 2004/2005
Biophysical elementary processes and
their dynamics
There have been three main research subjects under this project we
were focused on in the period of 2004–2005.
Mechanisms of Spectral Fine-Tuning
in Bacterial Photosynthetic Antennas
The ways photosynthetic organisms, plants, algae, and bacteria,
harvest solar energy and adjust efficiently to environmental extremes
has been of considerable interest over a long time already. This steady
interest is partly fueled by the hope of finding new biomimetic
principles applicable in synthetic molecular devices. The modern
history of solar energy transfer and trapping in photosynthesis can
perhaps be traced back to the work of Franck and Teller almost 70
years ago. Subsequent studies have established a concept of an
energetic funnel formed in photosynthetic membranes by the
specialized pigment-protein units that carry self-explanatory names of
antenna and reaction center complexes. According to this concept the
arrangement of the electronic transition energies of the pigments is
generally ordered, so that the pigments closer to the reaction center
sink absorb progressively more red-shifted light from the solar
spectrum.
The photosynthetic bacteria match best this simplified view of the
funneling photosynthetic unit. In all species of the purple photosynthetic bacteria the reaction center is encircled by a core or LH1
antenna complex. In many of them also a network of peripheral LH2
antenna complexes exists next to LH1. If to add that high-resolution
crystal structures are present for both the reaction center and LH2
antenna complexes, it becomes understandable why bacterial and not
plant species have been distinguished as the main test ground for
detailed understanding of the factors governing the spectral properties
of antennas and reaction centers.
Scientific Report • 87
Closely packed but non-covalently bound molecules constitute the
photoactive part of most photosynthetic complexes. The protein
frame is believed to provide a general structural support preventing
the pigment aggregates falling apart, but also to affect the electronic
properties of the pigments by supplying them individual binding
sites. Previous investigations have demonstrated a great role of
pigment-pigment and pigment-protein interactions in modification
of spectral properties of the bacterial antennas. The pigment-protein
interactions are the source of the so-called solvent shift of transition
frequencies of the pigments. Just like in common molecular solutions,
bonding to the surroundings can be broadly divided to non-specific
van der Waals couplings and to specific ones such as hydrogen bonds.
The various interactions between the pigment molecules that lead to
collective excitations delocalized over many molecular units may all
be classified as excitonic.
Spectral manifestations of the solvent shift interactions in LH1
and LH2 antenna complexes are numerous. The excitonic effects,
however, are much less firmly established. This lack of knowledge is
partly due to high spatial symmetry and partly because of inevitable
disorder (static as well as dynamic) of the antenna structures. The
LH1 and LH2 complexes possess similar circular arrangement of
tightly packed (the inter-pigment distance comparable to the
molecular size of ~0.9 nm) bacteriochlorophyll a (Bchl) molecules as
the main photoactive pigments. The transition dipole moments for
the lowest-energy Qy electronic transitions of the molecules in both
structures rest almost in the plane of the ring. The quantum
mechanics then rules that only two degenerate exciton states (the
second and third lowest) out of the total 32 (LH1) or 18 (LH2) states
reveal themselves in the linear absorption spectrum. The rest of the
states are dark, i.e. not accessible from the ground-state absorption.
While the variations of the surrounding matrix to some extent
mitigate this symmetry-controlled selection, they equally confuse the
assessment of genuine characteristics of the exciton.
88 • Biannual Report 2004/2005
Using polarized fluorescence excitation spectroscopy, we succeeded in determining the bandwidth of the exciton manifold in the
LH1 and LH2 complexes purified from the purple bacterium Rhodobacter sphaeroides. The model simulations based on experimental
crystal structures also allowed the weak high-energy exciton band tail
to be revealed for the first time. Still the relationship of the solvent
shift and exciton coupling components in spectral fine-tuning
remained elusive.
To work out this problem, advantage is taken from the fact that
some strains of purple bacteria develop special variant of the
peripheral antenna complexes named LH3, spectroscopically distinct
from the regular LH2, when growing under stressed conditions, e.g.,
low light intensity or low temperature. In the LH3 complex from
Rhodopseudomonas acidophila strain 7750 the lowest-energy
absorption band maximum is at 820 nm, almost 50 nm (or 700 cm–1
in energy) blue-shifted with respect to its position in the lowtemperature spectrum of LH2. We determined that almost no change
of the exciton couplings accompanied this shift (exciton bandwidth in
LH3 is less than 10% narrower compared with that in LH2). This
implies that the blue shift should be mainly attributed to the changes
in bonding patterns between the coupled Bchl molecules and the
protein. A comparison of the high-resolution crystallographic
structures of the antennas, which clearly demonstrates changes in the
hydrogen bond network, supports this interpretation. This way the
important roles that the protein and the neighboring pigments
separately play in modulation the characteristics of the lightharvesting systems have been revealed for the first time. We hope that
these studies may prove useful for understanding nanoscale molecular
assemblies as well as for designing more efficient light-harvesting
devices. [19, 67, 68, 79, 205, 218]
Scientific Report • 89
Pressure-Tuning Spectroscopy as a Tool for Investigations
of Intermolecular Interactions
In natural conditions the chlorophylls and bacteriochlorophylls form
readily complexes with a variety of other molecules, including
solvents. A traditional approach to study the interactions of solute
electronic surfaces with the solvent is by measuring the shifts and
shapes of optical spectra employing different solvents. However, this
method is subject to serious shortcomings due to the discontinuous
change of bulk physical properties and microscopic chemical composition of the solute environment when varying the solvent. In
contrast, by applying external hydrostatic pressures, continuous
tuning of solution properties over considerable range can be achieved.
When combined with optical spectroscopy, this technique provides a
very promising barochromic alternative for the solvation studies. The
conventional solvation models operating with macroscopic experimental parameters, such as the dielectric constant of the solvent,
generally fail in explaining the electronic level shifts and transition
energies, least the geometry changes of the molecules, due to
variations in the coordination number occurring during the solvation.
The atomic level approaches based on quantum chemistry are
therefore necessary for calculations of these effects. Due to the size of
the systems considered (140 atoms even without any solvent) the
quantum chemical methods of higher accuracy (ab initio at Hartree
Fock (HF), post-HF or DFT level with reasonably large basis sets) are
unfortunately not applicable, especially for modeling solvent effects as
a function of pressure. While the spectra of different chlorophylls
have been calculated at various levels of sophistication for unsolvated
molecules and molecules in complex with a few solvent molecules, to
our knowledge, no previous modeling of pressure dependent solvation effects has been done.
We have performed the atomic level simulations of the hydrostatic
pressure effects on the absorption spectra of chlorophyll a and
bacteriochlorophyll a in diethyl ether solution. The methodology
90 • Biannual Report 2004/2005
combining CHARMm, PM3 and ZINDO/CI methods yields results
in good agreement with the experimentally observed spectra, explaining the behaviour of the barochromic shifts of the Qy, Qx and Soret
bands up to 9 kbar. The simulations also reveal important aspects of
solvation effects and their pressure dependence. Close agreement with
the experimental data shows the potential of the method and
encourages for future studies in more complex environments, including native protein surroundings of photosynthetic complexes, our
ultimate goal. [16, 21, 216]
Photosynthetic O2 evolution from leaves
at wavelengths beyond 680 nm
The quantum yield of photosynthesis, calculated per absorbed light
quanta, drops at the red end of the absorption spectrum of leaves and
green algae. This drop can be compensated with the help of an
accompanying illumination at shorter wavelengths, a phenomenon
known as Emerson enhancement effect. The reason of the red drop is
the unequal distribution of excitations between the two photosystems, photosystem II (PSII) and photosystem I (PSI), which
operate as a tandem. For stable operation with high efficiency, electron transport rates through the two photosystems must be closely
equal that requires similar excitation rates. The antenna system of PSI
contains a number of so-called far-red chlorophylls (Chls), which
absorb at wavelengths beyond 700 nm. As a result, the far-red light is
mainly absorbed by PSI. Since the rate of electron donation to PSI is
determined by PSII, which is insufficiently excited, it strictly limits
the overall quantum yield of photosynthesis at the far-red end of the
Chl absorption spectrum. Occurrence of similar far-red Chls in the
PSII antenna is not recognized, though O2 evolution at wavelengths
beyond 700 nm has been reported and the optical cross-section of the
responsible Chls has been calculated. Since this cross-section was very
small at 723 nm, it was assumed to be a tail of the Chl a absorption.
Scientific Report • 91
Though the red drop has frequently been discussed in earlier
photosynthesis research, the extension of oxygen evolution to the farred end of the spectrum was seldom emphasized. After the zirconiumbased oxygen analyzer was taken into the armament by photosynthesis researchers, precise measurements of O2 evolution became
possible from the leaves. Applying the zirconium analyzer for the O2
evolution measurements and a tunable laser for illuminating the
leaves, we were revisiting this classical problem. A distinctive aspect of
our approach was that the leaves attached to the growing plant were
used in order to avoid changes that may occur upon disruption of the
leafs or cells. This way the light-activated O2 evolution from the
sunflower leaves at extraordinarily far-red wavelengths up to 780 nm
were measured. The quantum yield of O2 evolution has a local peak
at 745 nm almost reaching 20% of the maximum yield of 0.39 at
650-nm excitation. The similarity of the result for the sunflower and
bean proves that both the extreme long-wavelength oxygen evolution
and the local quantum yield maximum are general properties of the
plants. The observations were discussed in terms of as yet undisclosed
far-red forms of the chlorophyll in the photosystem II antenna,
reversed (uphill) spillover of excitations from PS I antenna to the PS
II antenna, as well as absorption from the thermally populated vibrational sub-levels of photsystem II chlorophylls in the ground
electronic state. [194, 195]
Compiled by Arvi Freiberg
92 • Biannual Report 2004/2005
Environmental radioactivity and radiation dose
in Estonia
Collection of soil samples and their gammaspectrometric analysis was
continued in order to determine the depth profiles of man-made and
natural radionuclide concentrations and the radon emanation
coefficients. Besides the Ra-rich areas in NE Estonia, the samples
were collected also from other regions of Estonia, characterized by a
medium Ra-content.
In collaboration with the Kiirguskeskus (Radiation Centre) the
analysis of the aerosol filter samples was continued, yielding the data
of 210Pb and 7Be content in air and its temporal variation in three
Estonian sites (Harku, Tõravere, Narva-Jõesuu) in 2001–2005. The
samples have been collected with the high-volume air samplers. The
radionuclide concentrations in the soil and aerosol filter samples were
determined by the low-background gammaspectrometry, using two
HPGe spectrometres. The purchase of a sensitive HPGe spectrometer
equipped with a planar detector GPD-50400 (BSI, Latvia) was
financed by an Estonian-Danish joint radiation protection project
and it was implemented in 2004. This instrument replaces the former
low-efficiency planar detector spectrometer. In 2005 a new basic
instrument, a contemporary portable HPGe gammaspectrometer
InSpector 2000 (Canberra, USA) was implemented and the gamma
spectrum analysis software GENIE2000 was mastered (K. Realo).
1. Radionuclides in soil
a) 210Pb. Characteristic for the soil in NE Estonia is the variation of
U/Ra rich regions and precipitation of radionuclide containing fly
ash, produced by the long-term exploitation of local power stations.
The formerly established 238U dilution (reaching in some locations
57% of the 226Ra concentration and a remarkable Pb deficite relative
to the same radionuclide in the highly Ra-contaminated regions
causes some difficulties as to unambigous interpretation and
Scientific Report • 93
modelling of 210Pb depth profiles. Therefore, the depth profiles were
sampled in two groups: from the areas with possibly low Ra
concentration in vicinity of the big power stations, and far from them
(> 10 km). The obtained 226Ra activity concentrations varied in the
interval 14–35 Bq kg–1 and the corresponding Rn emanation
coefficients fell into the limits 0.1–0.6. The 1-D diffusion model was
improved to separate the supported and unsupported 210Pb fractions
in the depth profile and to improve the precision of the corresponding migration parameters. About 67% of the Pb unsupported
fraction is found in the surface layer of 0–10 cm. In addition to the
diffusion model, a 4-compartment transport model was introduced to
describe the time-dependent migration of 210Pb from the soil surface
to deeper strata. The transfer rates in the set of differential equations
of the model have been found, fitting by the Scientist 2.01 software
the partial activities determined from the analysis of the soil samples
to the solutions of the model. The mean atmospheric concentration
of 210Pb in air of Narva-Jõesuu (located ca 20 km from the power
stations and the Ra-rich regions) was used as an input parameter. The
arithmetical mean concentration was 0.453 mBqm–3 and geom. mean
0.387 mBq m–3. For both models the transfer parameters were
determined for both depth profile groups. In general, the found
transfer rates for two soil groups are approximately equal. Thus, the
migration in soil follows nearly the same kinetics and only the the
mean deposition fluxes differ. The average downward migration
velocity of 210Pb into deep layers is ~0.27–0.30 cm a–1.
In the region, less contaminated by flyash, the 210Pb mean
atmospheric deposition flux is 164 Bqm–2a–1 and the mean deposition
velocity equals to 12 mms–1. At the same time, for the second group a
higher deposition flux of 321 Bqm–2a–1 was obtained. This can point
to the enhanced deposition velocity, or, most probably, to an
enhanced 210Pb content in air near the power stations. The observed
high deposition fluxes (and deposition velocities) support an
94 • Biannual Report 2004/2005
assumption about industrially enhanced 210Pb inventory in soil at sites
near the power plants (K. Realo, E. Realo, R. Koch).
b) 134Cs ja 137Cs. Our studies (1991–1993) of the activity concentration in soil depth profiles, induced by the Chernobyl accident,
yielded a simple monoexponential distribution with the relaxation
lengths in the region of 1.5..3 cm as a sufficiently good approximation. The depth profiles, obtained in 1998–2003 by
2–3 cm sections down to the depths of 20 cm, were analysed. The
Chernobyl contribution in the 137Cs content was computed from the
134
Cs analyses. The depth profile analysis confirmed the migration of
137
Cs into the deeper soil layers: the dependence of concentration on
depth is not exponential any more and it displays below- surface
maxima. It turns out that the general form of the 1D diffusionadvection migration in the case of a short term deposition (see, eg
[P. Bossew, G. Kirchner. J. Environm. Radioactivity (2004) 73,
127–150]) can be successfully approximated by a simple normal or
log-normal model. Using the latter, the determined 137Cs concentrations in depth profiles were fitted and the time-dependent parameters, xc and w, of the log-normal model were obtained. These
parameters demonstrate approximately linear time dependences. The
internationally accepted model RP72 gives the same result, except the
short time interval immediately after deposition. The compartmental
modelling was also exploited to determine the values of the advection
rate v and the diffusion coefficient D, which can be compared to the
parameters of the 1D model. (M. Lust, K. Realo, E. Realo).
2. 7Be and 210Pb in air
7
Be is a cosmogenic radionuclide, produced by cosmic radiation
induced nuclear reactions involving oxygen and nitrogen atoms in
stratosphere. Its migration into the near-surface air is due to the
descending air masses. 210Pb is a long lifetime daughter product of
222
Rn, The released radon atoms from soil particles are transported by
advection and diffusion through the pores and a fraction of them is
Scientific Report • 95
released into the atmosphere. Radon nuclei undergo a number of
decays to produce 210Pb, which migrates with air masses, is spread by
turbulences, etc. Simultaneous study of the 7Be and 210Pb concentrations gives significant information on the transfer of radionuclides
in the environment, as well as on the dynamics of physical processes
in the atmosphere (7Be is formed in the stratosphere and 210Pb in the
troposphere, different sedimentation processes, etc.). All the above
features have made these studies attractive for applications in
atmospheric transport and removal processes, oceanography and
sedimentation, geophysical dating. It should be underlined that their
content in air depends significally on the regional and local weather.
The three high-volume filter samplers are situated rather appropriately in Estonia. Ca 650 air filter samples have been analysed. Up
to now we have data for the years 2001–2005:
a) weekly 210Pb and 7Be mean concentrations in air and temporal
variations in three locations (Harku, Tõravere, Narva-Jõesuu);
b) meteodata for the same locations;
c) the data on the area dose rates.
Establishing of the corresponding correlations/regressions is started
and being continued.
The first conclusions, needed for development of a general model
of the transfer of these nuclides in the Estonian environment, are the
following:
– The air concentrations near the sea (Harku and Narva-Jõesuu) are
smaller than in the inland (Tõravere): Rn does not emanate from
the marine environment; for 7Be we found a significant negative
correlation with the air humidity.
– The ratio of 7Be and 210Pb concentrations varies widely from 0.6
to 16.6 in all sampling sites. It reaches maxima in summer as a
result of thermal convection upon 7Be transport, together with
the descending air masses from the higher atmospheric layers. In
96 • Biannual Report 2004/2005
winter, the ratio is minimal, while 210Pb has an enhancement
trend.
– The air temperature and air pressure have the greatest effect upon
the 210Pb concentration. The magnitude of air pressure 3–5 days
before the sampling interval influences its concentration more
than the value during sampling. The wind speed diminishes the
210
Pb concentration mostly.
7
– Be content correlates significantly with air humidity and air
temperature.
– The regional weekly mean dose rates at the sampling sites
practically do not correlate with neither 7Be nor 210Pb content in
air.
Performing of multivariant regressions of the data is under way. As
part of the weather parameters are correlated, the Pearson correlations
do not yield reliable results due to their collinearity.
3. Radionuclides in lichens and peat
Peliminary results were obtained, investigating contents of 137Cs and
natural radionuclides in lichens. The radionuclide content in the
objects, known as significant indicators, were compared with the
contents in soil samples, collected in the vicinity. The transfer factors
“soil-lichen” and “air-lichen” were established. This new research
subarea (MSc thesis of L. Aarik) explores the possibility of using
lichens for determination of environmental radionuclide activity
concentrations and finding the transfer factors between various
compartments of the environment. It is a novel trend in the field,
aimed at the elucidation of bioindicators for radionuclides in our
environment and at the finding correlations of 137Cs, 7Be and 210Pb
contents in lichens, air and soil. In the work by L. Aarik, the
radionuclide contents in the samples, collected in the vicinity of
Tõravere and Tartu, along with the related transfer factors, were
Scientific Report • 97
determined. Collection of samples from a wider area and their
analysis is in progress (L. Aarik, M. Kiisk).
4. Quality assurance in gammaspectrometric analyses, modelling
Elaboration and testing of the methods of preparation of lichen and
peat samples and analyse of them of radionuclides. The work is
underway, preliminary results are promising (M. Kiisk, L. Aarik).
Detection limits of low-energy low-intensity gamma-emitting
natural radionuclides, such as 230Th and 238U, by gammaspectrometric
analysis have been determined. The software for gammaspectrometric
analysis of U and Pu samples (obtained via project JRC ITU,
Karlsruhe) was tested (M. Kiisk, K. Isakar, K. Realo, T. Sisask).
The modelling software RESRAD for long-term radionuclide
migration was modified to take into account the inhomogeneity of
the radioactive wastes. It was applied to assess the radiological impact
of the interim depository of radioactive wastes in Paldiski for the time
spans up to 10000 years in the near-field and far-field exposure
pathways (in collaboration with the ALARA, Ltd.).
Different versions to dispose small sealed radiation sources mixed
with large amounts of conditioned low-activity wastes and the corresponding exposure pathways have been analysed. The results might be
useful to find the economical disposal options of high-activity sealed
sources and the conditions to be followed in designing containers/
waste packages (E. Realo).
Our participation in the intercomparison excercises of the Nordic
and the Baltic states NKS 2002/3 and RISOE 2004 (2004/5) gave
good results. The overall result in the 2002/3 excersise (published in
2004): the deviations were insignificant in the cases of all radionuclides. From 17 participating labs, we were among these 6 labs,
which passed the exercise. The results confirm the high analysis
quality and the advanced qualification of our analysts.
In a number of locations in Estonia the ground water contains
high levels of radium. This fact gives rise to health problems and
98 • Biannual Report 2004/2005
makes the adequate investigations actual. We elaborated the analysis
method and started the gammaspectrometric analysis of Ra in
drinking water and the dose assessment of internal exposures to the
population (supported by the contract with the Health Protection
Service of the Ministry of Social affairs).
In collaboration with the Central Laboratory of Health Protection, we reached acceptable results in the intercomparison exercise
on the radionuclide analysis in water samples, arranged in 2004 by
the Ministry of Social affairs (M. Kiisk, K. Realo, E. Realo).
The gamma radiation transfer software GEANT4 (CERN) was
applied for the Monte Carlo modelling of detailed interactions of
low-intensity low-energy gamma-rays for nuclides 210Pb, 230Th and
238
U in the complex source-detector geometry (K. Isakar).
A simplified model has been elaborated to compute the correction
factors, taking simultaneously into account different self-absorption
and sample height. The corrections were exact down to 1–2 %. The
model based on exact Monte Carlo modellings (K. Realo, E. Realo,
K. Isakar).
5. The polariton theory in the gamma-resonant spectroscopy
The propagation of the Mössbauer radiation was analyzed in terms of
the collective nuclear excitations, created in a resonant medium due
to multiple coherent scattering. The cooperative effects were investigated in two different situations: 1) propagation of resonant synchrotron radiation (SR) in the case of splitted Mössbauer levels and 2)
creation or decay of a stationary beam of nuclear polaritons (NP).
1. It has been shown that the primary pulse of SR, penetrating the
sample, creates a collective nuclear excitation in it. If the hyperfine
interaction is strong (level splitting exceeds the width of the
broadened absorption lines), the initial collective state is decomposed
very rapidly, due to dephasing, and independent nuclear excitons
(NE) arise instead of it. The number of NE (freely oscillating
ensemble of nuclear multipoles) equals to n (the number of different
Scientific Report • 99
Mössbauer transitions) and each NE is characterized by its frequency
and initial phase. Interference of the secondary gamma-quanta,
emitted by different NE, causes pronounced quantum beats of the
transmitted radiation intensity. However, this structure is modulated
by the dynamical (polariton) beating phenomenon. In the case of a
moderate or weak splitting, the initial collective nuclear excitation
decays as a single NE, creating NP in the sample. These NP are
characterized by the same group velocity and different frequencies.
The intereference of NP causes the beating of the transmitted
radiation, beating parameters determined by the NP characteristics.
During the process, the number of the interfering polaritons changes
from 2 to n+1.
2. In a resonant medium, a beam of Mössbauer radiation is
converted into a beam of NP (mobile nuclear excitations). We have
shown, that the photon-polariton conversion takes place in a finite
layer of the sample during a finite time interval, the corresponding
parameters depending on the radiation frequency. Furthermore, only
part of the coherent secondary radiation, created by the ensemble of
the excited nuclei, is represented by the polariton wave. The second
component, the screening field, prevents the primary beam from
penetrating into the bulk of the sample (quantum theory analog of
the Ewald-Oseen theorem in the classical optics) and is the reason of
significant effects in the rapid (non-adiabatic) transition processes. If
the primary beam is rapidly switched off, the screening field may
cause a short increase of the transmitted radiation. If the radiation
source is switched on, the screening field, as the most dynamical
component, determines the length of the precursor pulse. In both
cases, the further evolution can be described as the slow movement of
the polariton wave-front across the sample. Thereby the shape of the
front does not depend on the primary beam. These effects have been
observed in the Mössbauer time-domain experiments, the results
being in the agreement with the theory, developed in our institute.
Compiled by Enn Realo and Mati Haas
100 • Biannual Report 2004/2005
Theory of Fundamental Structure of Matter
The theoretical physics belongs to the traditional research fields of the
Institute of Physics. The topic of research project is rather broad; it
includes the theory of condensed matter, optics and spectroscopy, the
high-energy physics and general relativity. A characteristic feature of
the last 10 years is the essential increase of joint research with scientists from abroad, especially from Europe and United States; approximately half of papers are written in international collaboration.
The teaching of theoretical physics and supervision of students
and post-graduates in theoretical physics is also one of main goals of
the project.
Theory of elementary particles and gravitation
Braneworld cosmology
One of the main challenges for contemporary theoretical cosmology
is to explain the physical nature of dark energy, which may account
for up to two thirds of the energy density of the Universe. A possible
explanation can be found in the framework of the braneworld cosmology, where our Universe is one of two hypersurfaces embedded into a
5-dimensional bulk spacetime and a scalar radion field measures the
proper distance between the branes. Mathematically, the corresponding theory is a scalar-tensor cosmology with a nonconstant coupling
function. Our investigations demonstrate that the two-brane cosmological model in the first approximation of gradient expansion written
by Kanno and Soda [Phys. Rev. D66: 083506 (2002)] as a scalartensor theory with a specific coupling function can be understood as
describing two Friedmann-Robertson-Walker type cosmologies on
two branes. The only contact between the branes is established by the
constraint equation which determines an integration constant in the
first integral of the equation for the Hubble parameter of our
Universe in terms of an integration constant in the solution of the
Scientific Report • 101
equation for the second (hidden) brane. The value of the integration
constant can be interpreted as the value of the energy density of the
dark radiation at a fixed initial moment t0. Solutions for some special
cosmological models are found (solution with a constant dilaton field,
radiation dominated Universe with cosmological constant etc.). The
influence of the asymptotic nontrivial scalar field on gravitational
experiments in the Solar system encoded in the parametrized postNewtonian (PPN) parameters is estimated.
Anomalous gauge boson self-couplings
One method to test possible new physics (NP) beyond the Standard
Model (SM) is based on observation of small departures from the SM
predictions in processes, where the external particles are ordinary SM
ones, and NP effects can arise only from the anomalous (nonstandard) couplings. Among the most promising processes to which
anomalous couplings could contribute, is the process e+e–oZJ
Through this process the possible existence of anomalous couplings
between three neutral gauge bosons (ZZJ, ZJ ) can be tested. By
exploiting a method based on the use of general relativistic spin–1
density matrix used by us earlier [I. Ots et. al., Nucl. Phys. B 588
(2000), 90], we have evaluated and analysed the contributions from
possible anomalous ZZJ and ZJJcouplings to the spin orientation of
the Z boson in e+e–oZJ with longitudinally polarized (LP) and
transversely polarised (TP) initial beams. The main features of the LP
and TP contributions to the Z boson spin polarization vector and the
alignment tensor have been presented and their roles in disentangling
different sets of couplings (SM, ZZJ, ZJJ) have been clarified. It has
been shown that by using LP initial beams one can substantially
enhance the sensitivities to one or other couplings. However, LP does
not enable measurements of the parts of couplings which are, at least
in principle, inaccessible with unpolarised beams. Contrary to LP, TP
can enable such measurements. In the case of anomalous couplings,
simultaneously TP initial beams provide the theory with extra
102 • Biannual Report 2004/2005
directions due to which the Z boson polarization vector obtains
additional, out-of-reaction-plain components and new alignment axes
are added to the alignment tensor.
Since the orientation of the Z boson is transferred to the angular
distribution of its lepton decay products, one can put limits to the
anomalous couplings by probing the Z boson spin polarization and
alignment through the measurement of the shape of Z boson lepton
decay spectrum. For details see a special article on pp 26–29.
Theory of solid state, optics and spectroscopy
In the field of condensed matter, optics and spectroscopy the research
is performed in close collaboration with the experimental studies in
the institute. In years 2004–2005 main results were obtained in the
theory of vibronic transitions, nonlinear lattice dynamics, quantum
and singular optics, in the study of strongly correlated systems, and
phase transitions in crystals.
Nonlinear dynamics, optics and spectroscopy
Recent years studies have shown that strongly localized vibrational
excitations can exist in perfect nonlinear lattices. The frequency of
such a vibration depends on its amplitude and lies outside the
phonon spectrum. Such vibrations are called intrinsic localized modes
(ILMs), to emphasize their similarity in appearance to defect impurity
modes, or discrete breathers or discrete solitons to make a connection
to solitons in continuous systems. The discovery of this intrinsic
dynamical inhomogeneity should lead to other new features. In our
investigations we have found that the appearance of an ILM in the
lattice changes the local phonon dynamics. As a result of this back
reaction on the phonons the ILM induces appearance of linear local
modes (LLMs) outside the phonon spectrum. A theory is developed
for describing this effect in a monatomic chain with hard quartic
anharmonicity. To verify it, molecular dynamics simulations of vibra-
Scientific Report • 103
tions under strong local excitation have been carried through with
high precision. The numerical results fully confirm the prediction.
A general theory of the spin-dependent and spin-independent
longitudinal and transverse shifts at reflection of the light beam
carrying the orbital angular momentum is developed. In the case
when the incident beam is paraxial and s- or p-polarized, the following results have been obtained. The closed formula has been
deduced which describes the position of the center of gravity of the
reflected beam on the whole output plane, the position does not
depend upon of the dimension of the cross-section of the incident
beam. A method of the experimental definition of the transverse shifts
of such beams is proposed; the method is based on the difference of
the transverse shifts of the p- and s-polarized beams through a crosscorrelation function. It is shown that the change of the intrinsic
normal component of the angular momentum of the beam at
reflection must be accompanied by appearance the extrinsic one.
A theory of the dynamical Casimir effect,− the quantum emission
of a dielectric with periodically changing in time refractive index n
has been developed. The changes of n in time cause analogous
changes in time of the optical length. It is demonstrated that a resonant enhancement of the quantum emission takes place if the
maximum velocity of the changing in time of the length mentioned
approaches a critical value Vcr. Our calculation gives Vcr ≈ 3c.
Basing on the ideas of the Feynman path integrals, a new method
of calculation of optical spectra of impurity centres in crystals in the
case of an arbitrary quadratic vibronic coupling is proposed. In this
method, to calculate the Fourier transform of the spectrum the time
evolution of the final state of the transition is divided into a large
number N of time steps. Taking into account that the time evolution
between the steps is classical, the calculation of the Fourier transform
is reduced to the computation of the determinant of the N × N
matrix and its reciprocal matrix. The matrix elements are given by the
104 • Biannual Report 2004/2005
pair correlation functions of the contributing configurational coordinates. The method is verified for a system with two mixing modes.
A theory of vibronic spectra in the centres with strongly reduced
local elastic constants in the excited state has been developed. The
theory exploits the existence of a small parameter in this case the
ratio of the mean frequencies of vibrations in the final and initial
states. In this case the long-wave part of the phonon sideband of the
spectrum is strongly enhanced. The spectral line has strongly
asymmetric envelope with a peak at the frequency of the zero-phonon
transition; its shape is modulated. The origin of the modulation lies
in the effect known as the Airy oscillations.
The dependence of the spontaneous emission rate (SER) of a
single impurity molecule on the orientation of the dipole moment
with respect to the principal axes of the dielectric tensor of the host
crystal has been calculated for seven biaxial host crystals (anthracene,
chrysene, diphenyl, fluorine, naphthalene, phenanthrene, terphenyl).
The differences in the SER values in the same host crystal may attain
34%.
Strongly correlated systems, high-Tc superconductivity,
phase transitions
A model of a cuprate superconductors based on the electron spectrum
steaming from the doping of holes with the interband pairing channel
has been developed. This model reproduces the behavior of basic
superconducting characteristics in qualitative agreement with experiment in the whole doping scale. E.g. the calculated coherence length
depends non-monotonously on the hole concentration C in agreement with measurements. The dependence of the supercarrier density
and the critical magnetic fields on C follows the transition
temperature. In the under-doped case the effective mass of the
supercarriers slowly diminishes with C.
Scientific Report • 105
Basing on results obtained in the t-J model of Cu-O planes and
Mori’s projection operator formalism, the peak in neutron scattering
experiments at the antiferromagnetic wave vector in yttrium cuprates
has been interpreted as excitations of localized Cu spins. The highfrequency incommensurability detected in lanthanum and yttrium
cuprates is connected with the dispersion of these excitations, while
the low-frequency incommensurability arises due to a dip in the spinexcitation damping at the antiferromagnetic wave vector. For moderate doping the dip stems from the weakness of the interaction
between the spin excitations and holes near hot spots.
The diagram technique for the one-band Hubbard model is
developed for the case of moderate to strong Hubbard repulsion. The
expansion in powers of the hopping constant is expressed in terms of
site cumulants of electron creation and annihilation operators. For
Green's function an equation of the Larkin type has been derived and
solved in a one-loop approximation for the case of two dimensions
and nearest-neighbor hopping. At half-filling the obtained four-band
structure of the spectrum is close to that observed in Monte Carlo
calculations. With decreasing electron concentration a new narrow
band of the spin-polaron type arises in the energy spectrum near the
Fermi level.
The anomalous enhancement of the dielectric constant by both
the UV and DC electric field has been found in quantum paraelectrics of perovskite oxide types. A gigantic increase of the dielectric
constant in UV light and DC electric fields is connected with the
renormalization of effective charge by the soft mode. The timedependent Ginzburg-Landau equations in cuprates have been derived
for the case of two-order parameters and the pseudogap. The relaxation times of the order parameters and pseudogap have been found.
n
The coupling of F1u vibrations with the electronic states of BO6
cluster in ABO3 ferroelectric-oxides leads to the dynamical covalency
hybridization of B(Ti,Ta,Nb) and oxygen electronic states. The
106 • Biannual Report 2004/2005
n
adiabatical potential for BO6 (n=6,8) has been obtained. The offcenter displacement of B ions has been calculated.
Compiled by Piret Kuusk, Ilmar Ots, and Vladimir Hizhnyakov
Laser physics and laser-optical technologies
Research and development within framework of this theme carries on
the Institute’s traditionally strong studies in the field of low
temperature spectroscopy, wave optics, nonlinear and laser spectroscopy, photophysics and photochemistry of laser active media as well
as development of associated experimental equipment and technologies in cooperation with local small high-tech companies. Some
main results on localization of photon wavepackets had been introduced already in Section “Research Highlights” in the papers by
P. Saari and V. Peet.
Luminescence of Ȗ-radiation-induced defects
in Į-quartz crystals
Optical transitions of point defects play a crucial role in applications
of silicon dioxide (SiO2). The transitions associated with -radiationinduced defects in crystalline -quartz have been investigated by
photoluminescence methods. These studies have been carried out in
collaboration with researchers from Latvia and Italy. Synchrotron
radiation and steady-state light have been used for the excitation of
luminescence. Two characteristic emission bands have been established as a result of 10 MGy -dose: an ultraviolet band at 4.9 eV and
a blue band at 2.7 eV, both being excitable in the range of the
induced absorption band at 7.6 eV. Both these emissions decay in the
time scale of few ns under pulsed excitation, while the blue band can
also be observed in slow recombination process, and it afterglows in
about 100 s at the end of steady-state excitation. [11]
Scientific Report • 107
Electron transport properties of low-dimensional systems
Miniaturization of components is a trend in microelectronics, which
is closely related to the effects of quantum interference and the
phenomena of decoherence of conduction electrons. In this context
studying the electron transport properties of the compounds
Nb4.77Te4 and Ta1.2Nb3.4Te4 with quasi-one-dimensional crystal
structure is certainly of interest. These studies have been performed
using monocrystalline samples of 3–5 mm length and
0.005–0.05 mm2 cross-section. Measurements involved temperature
range from 0.3 to 270 K and the magnetic fields up to 11 T.
Nb4.77Te4 belongs to the compounds crystallizing to the tetragonal
Ti5Te4 structure type. It undergoes a transition to superconductivity
at critical temperature Tc = 0.6–0.9 K. In the normal state a nonmonotonic temperature dependence of the resistivity was observed,
and two characteristic local maxima at T ≈ 2 and 30 K have been
ascertained. The position of the low-temperature maximum correlates
with Tc, which has been interpreted as an interplay of electronelectron interaction in the diffusion and Cooper channels. The hightemperature maximum can also be interpreted in terms of the interference effects as a result of competition between the weak localization and the weak antilocalization of conduction electrons. The
magnetoresistance data have been interpreted according to the MakiThompson-Larkin effect and electron-electron interaction in the
Cooper channel.
The compound Ta1.2Nb3.4Te4 has a monoclinic crystal structure,
being a superconductor with Tc = 1.3 K. In the normal state the
magnetoresistance is determined by the quantum interference effects.
The dephasing time of conduction electrons extracted from the
magnetoresistance data was determined by the electron-electron
interaction. Similar to Nb4.77Te4 the temperature dependence of the
resistivity in Ta1.2Nb3.4Te4 is nonmonotonic but with two maxima at
4 and 14 K.[215]
108 • Biannual Report 2004/2005
Localized electromagnetic waves
The scalar free-space wave equation has a class of solutions that
seemingly defy the laws of diffraction and can preserve very sharp
spatial and temporal localization in the course of propagation over the
distances that many times exceed the Rayleigh range. During the past
few years the experimental generation of localized waves has been put
in solid terms and we have moved on in two directions: (i) finding
new theoretical models of strongly localized waves for realization in
the optical domain, (ii) transferring the know-how obtained in
working with classical fields into the domain of quantum optics. The
following main results have been obtained.
Simple practical model approximations to the so-called focused X
wave – a pulsed wave propagating superluminally in vacuum or in a
linear medium, which attracts attention due to its spread-free strong
spatial localization – have been derived. The experimental feasibility
of the model waves in the optical domain has been shown and their
radial decay analysed.
In contradistinction to a widespread belief that the spatial localization of photons is restricted by a power-law falloff of the photon
energy density we have shown that for certain specifically designed
cylindrical one-photon states the localization is exponential or even
better in lateral directions. If the photon state is built from the socalled focus wave mode, the falloff in the waist cross-section plane
turns out to be quadratically exponential (Gaussian) and such strong
localization persists in the course of propagation [206]. More detailed
overview of these results the reader can find in Section “Research
Highlights” of this Report.
Multiphoton processes in intense laser fields
In recent years, interesting and unusual features of the so-called
nondiffractive or propagation-invariant light beams have attracted
considerable interest in applications of such beams in nonlinear
Scientific Report • 109
optics. In most cases the simplest coherent conical beams like Bessel
beams were used, but much less is known about nonlinear optical
processes driven by incoherent conical beams. Recently several
evidences have been found that conical excitation geometry allows
one to preserve a relatively high efficiency of a nonlinear process even
for laser beams with significantly degraded beam quality. Such a
tolerance may be very interesting and useful feature of conical beams
in the excitation of nonlinear optical processes and frequency conversion of laser emission.
Resonance-enhanced four-wave mixing and generation of sumfrequency field in xenon have been studied under two-color excitation
by spatially coherent and incoherent conical laser beams. Comparisons of analogous results with a two-color excitation in an ordinary
geometry of focused beams and in one-color Bessel beams have been
made. It has been shown that with incoherent laser beams the fourwave mixing process is much less degraded in conical excitation
geometry where an efficient generation of sum-frequency field can be
obtained despite of multiple wave-front aberrations. Such a tolerance
of conical beams results from their specific structure of coherent focal
domains that are extended significantly along the beam axis. It
preserves a relatively high degree of coherence for excitation processes
even for input beams with poor spatial coherence. Numerical
simulation of sum-frequency excitation profiles for one- and twocolor conical beams has been carried out and good agreement with
experimental observations has been obtained.
Spectroscopy of plasmo-chemical processes in the active
media of discharge pumped UV-VUV gas lasers
The high-current powerful (~50 MW/cm3), pulsed (~10 ns)
homogeneous volume discharge in high-pressure (up to 10 bar) argon
has been comprehensively investigated with ns time-resolved spectroscopic diagnostic techniques. Importance of this subject is connected
with the development of efficient excimer light sources and possible
110 • Biannual Report 2004/2005
using of rare gases discharge plasmas as VUV laser active media. The
aim of this work is revealing of energy flow kinetics in high-pressure
discharge plasma. Spatial-time behaviours of the main excited atomic
species and electrons were monitored from VUV-VIS spontaneous
emission spectra of the discharge. It was revealed, that broad
(200–850 nm) UV-VIS continuum is caused mainly by photorecombination of electrons with Ar2+ ions. Emission intensities from
this continuum and red Ar* lines have a typical recombination
behavior in the afterglow stage of the discharge (square root of its
intensity is proportional to the electron density).
Time dependences of Ar* (4S, 4P), Ar2*(36u) densities were
measured by the pulse dye laser absorption probing of the discharge
plasma. Quantitative experimental data about densities of key excited
atomic and molecular species are very important for understanding of
discharge pumping efficiency and how close to the lasing-threshold
conditions we are able to approach in our real discharge devices.
Experimentally obtained temporal dependencies of several excited
species are compared with calculated ones.
Strong optical dynamic aberrations in the discharge plasma are
observed for the probing laser beam at high pumping power density
conditions. These phase aberrations is caused by negative contribution of free electrons to the refraction index. Possible mechanisms
responsible for the experimentally observed saturation of Ar2* VUV
(126 nm) emission output with increase of the pumping power were
analysed on the basis of received plasma parameters. Optical dynamic
aberration could be the main limiting factor for using of discharge
plasma as a laser active medium at high pumping power density
conditions.
Scientific Report • 111
Stark absorption spectroscopy of indole and
3-methylindole
Electroabsorption (EA) or Stark effect spectroscopy implies the measurement of the spectrum of a small (~0.1%) change in sample
absorbance induced by a strong (~1 MV/cm) externally applied
electric field. According to the theory, which takes into account the
Stark shift of the transition frequency and the field-induced reorientation effects for a mobile ensemble of polar absorbing molecules at
thermal equilibrium, the change in absorbance scales quadratically
with the field strength and the EA spectrum of a given band can be
expressed as a linear combination of the zeroth, the first, and the
second derivatives of the absorption spectrum of that band.
We analysed room-temperature UV (240–320 nm) absorption
and EA spectra of biomimetic molecules indole and 3-MI, doped into
a polymethylmethacrylate (PMMA) film. By a model fit the
simulated EA and absorption spectra to the measured ones, the
spectra are decomposed to the contributions from threeSS* type
singlet electronic transitions (to the La, Lb, and Bb excited states) and
several molecular parameters, for example the change in permanent
dipole moment and the change in polarizability accompanying the
transition to the La state, are obtained.
Analysis of the changes in the shape of the EA spectrum as a
function of the angle between the polarization direction of the
absorbing light and the direction of the applied electric field proved
that polar indole and 3-MI molecules are partially reorientated
towards the electric field in the room-temperature PMMA matrix.
Measurements at 50K, where the angular mobility of indole and
3-MI molecules in PMMA is doubtlessly frozen, confirmed the
absence of field-induced orientation/alignment effects in the EA
spectra. [240]
112 • Biannual Report 2004/2005
Laser physics outside physics – copper vapour laser
system for medical applications
Efficacy of treatment in nowadays medicine essentially depends on
the development of technology. This general rule also applies to the
laser medicine, and more specifically, to the lasers used for the cure of
skin diseases. A copper vapour laser (emitting at 511 and 578 nm) has
been used for this purpose already for 10 years in the Dermatological
Clinic of the University of Tartu. This original laser system has been
designed and manufactured as a result of fruitful collaboration
between the Institute of Physics (IP) and the Estonian laser firm
“Estla”. Results of the laser treatment of various skin diseases (acne,
allergodermatoses, leg ulcers, etc.) as well as skin defects (teleangiectatic lesions) have been very good (see Fig. 1): the percentage of
recovery exceeds 70. No side-effects have been noticed, the laser
emission is well tolerated by the patients and it does not interact with
systematic or topical medicines. Laser cure has been introduced as a
standard method of treatment in the Dermatological Clinic
(15–20 patients per day). Two years’ experience in the Clinic of small
domestic animals shows that the green and yellow Cu laser emission
with intensity of 200 mW is also very effective in the cure of skin
diseases and other inflammations of domestic animals (dogs, cats,
rabbits, etc.).
An essential step forward (achieved in collaboration between the
IP and “Estla”) was the implementation of a more powerful (3 W) Cu
laser in the Dermatological Clinic. This new laser is provided with an
electronic shutter, which enables pulsed (from 0.1 to 1 s) irradiation
of skin defects. Therefore, relaxation of heat occurs during the pauses
between the pulses, which means that the higher intensity of the
irradiation can be used. Consequently, skin defects can be removed
more quickly and more utterly.
The patient, a 30 years old
car locksmith, was suffering with allergodermatosis.
x First picture shows the
situation before the laser
cure was initiated.
x Two days after the first
30 minutes’ laser
treatment.
x Five days after the
second 30 minutes’ laser
treatment.
Figure 1. Demonstration of the efficacy of Cu laser treatment.
Figure 2. Explicit demonstration of the Levinson theorem
(¥(0) -¥(∞) = Nπ) for Xe2. As needed,¥(0) = 24π, since the system
has 24 bound states. At E = 3.146294 meV, the phase shift passes a
zero, it has a minimum at E ≈ 2932 eV, and very slowly approaches
the limit (¥(∞) = 0) as E ∞. The left-side inset shows nearly linear
dependence on the wave number k as E =ʄ2k2/2m 0, in full
agreement with general-theoretical concepts. In the right-side inset
one can see that the phase curve has an inflection point near V(0) (the
potential energy at the origin).
Scientific Report • 113
A new approach to the inverse problem
in quantum mechanics
One-dimensional inverse Schrödinger problem can be solved, i.e., the
interaction potential for a confining one-dimensional quantum
system can be uniquely determined, if and only if the following
complete set of information is available:
x Full energy spectrum of the bound states (En < 0, n = 1, 2, …,
N).
x Full energy dependence (from 0 to ∞) of the phase shift (E)
for the scattering states.
x N additional real parameters related to relevant bound states
that uniquely fix their normalization.
Unfortunately, all these obligatory data are never available. In this
situation, one may try to construct a reference potential, whose spectral characteristics should be in a reasonable agreement with available
data on the system's properties. Since the reference potential is fixed,
it is always possible to calculate all its spectral characteristics, including the phase shift for the full range of scattering states, and the Jost
function. Such an approach has been developed on example of
diatomic xenon molecule in its ground electronic state. An exactly
solvable reference potential for this system has been constructed,
which enables to solve the related energy eigenvalue problem exactly.
Moreover, the full energy dependence of the phase shift can also be
calculated analytically, and as a particular result, full agreement with
Levinson theorem has been achieved and explicitly demonstrated (see
Fig. 2).
Provided with full spectral information about the reference
potential, one can, in principle, calculate an improved potential for
the system. For example, one can construct a potential whose bound
states would coincide with the “real” discrete energy levels. To this
end, a two-step scheme has been proposed which combines the well-
114 • Biannual Report 2004/2005
known Gelfand-Levitan and Krein methods for the solution of the
inverse problem. [264–267]
Compiled by Peeter Saari
Fundamental phenomena in wide-gap materials and
their prospects of application
The main aim of the present project (2002–2006) was to investigate
the fundamental peculiarities of relaxation, localization, decay and
multiplication of electronic excitations (quasi-particles) in wide-gap
(Eg=5–15 eV) inorganic dielectrics, based on metal oxides and halides,
and to analyse the usage prospects of these processes for elaborating
new and improving the existing dielectrics, widely used for various
technical applications.
One of the main aspects of investigations in 2004–2005 was the
elucidation and experimental testing the prospects for increasing the
radiation resistance of construction materials for tritium-deuterium
fusion reactors. The planned experimental and powerful industrial
reactors have several advantages with respect to nuclear reactors based
on fission of heavy nuclei. Thermonuclear energetics is alluring not
only due to extended reproduction of fuel (hydrogen isotopes); it is
also environmental-benign (there is no release of CO2 responsible for
“greenhouse” effect, other unhealthy gases and radioactive waste) and
secure against terrorist attacks. However, the radiation resistance of
the existing materials for powerful fusion reactors is on its breaking
point and should be significantly increased. The another priority of
our applied research was determined by the contracts with
SAMSUNG SDI (since 2005) connected with the research and
development of plasma display panels (PDP) used in large-dimension
modern TV sets, where scanning electron beam is replaced by point
discharges of xenon emission (vacuum ultraviolet (VUV) resonant
Scientific Report • 115
emission at 8.43 eV). New dielectric materials with lower discharge
firing voltage has to be elaborated and VUV xenon emission should
be transformed into green, blue and red light with optimal characteristics by means of radiation-resistant spectral transformer.
Particular emphasis has been placed on radiation-resistant binary
metal oxides and fluorides promising for thermonuclear energetics,
PDP and new generation of fast detectors and selective dosimeters of
radiation. Basic peculiarities of the processes of relaxation, localization, multiplication and decay channels (with emission, heat release
and especially with the creation of structural defects) of electronic
excitations (EEs) have been investigated in binary wide-gap materials
with simple structure – LiF, BaF2, MgO and various modifications of
Al2O3, glasses and crystals of SiO2. The peculiarities of energy spectra
and radiation processes in more complex systems – metal tungstates
and suphates (Me = Mg, Ca, Sr, Ba, Pb), lithium silicates, aluminates
(BaMgAl10O17, Ca12Al14O33, Lu3Al5O12, etc) have been studied as
well. In these materials the energy gap Eg varies in a wide range and,
in contrast to metal halides, the v-band is complex and energetically
wide (Ev = 4–10 eV) resulting in important features of hole processes.
The main distinctive feature of our experimental approach is the
usage of the exciting photons in a wide energy range (5–2000 eV,
incl. synchrotron radiation facilities of MAX-lab, Lund and
HASYLAB at DESY, Hamburg), electrons of various energies
(1–300 keV) and a wide temperature range of experiments (1–750 K)
by means of the methods of optical, X-ray, electron, time-of-flight
mass and thermoactivation spectroscopy, and EPR method. The
study of wide-gap crystals and thin films of several types using VUV
and XUV (soft X-ray) photons turned out to be very informative.
Such photons cause a selective creation of EEs in inner and outer
cation shells, oxygen ions, complex oxyanions as well as the formation
of groups of several spatially correlated quasi-particles. The peculiarities of the processes of relaxation, self-trapping and decay of anion
and cation excitons have been revealed and the features of hole
116 • Biannual Report 2004/2005
processes have been investigated for the first time in metal oxides with
wide and structured v-band. Several novel effects have been revealed
in wide-gap materials under conditions of high-density irradiation by
powerful electron pulses or heavy swift ions. The effects connected
with high density of excitations are particularly important in the
search for increasing the radiation resistance of materials for fusion
reactors, optical windows for short-wavelength lithography and for
selective dosimetry of fast neutrons and novel fast scintillators.
The results obtained in 2004–2005 were published in 67 articles
(including 45 CC contributions) and presented at 16 international
conferences (19 talks, 4 of those invited, and 27 poster presentations).
The main results can be divided into several groups as follows.
Defect creation by hot electron-hole recombination in oxides
Among binary crystals there are several wide-gap oxides (MgO,
Al2O3, SiO2 etc.) whose radiation resistance against X-irradiation is
hundreds times higher than in alkali halide crystals. Such difference is
conditioned by the fact that the creation energy of Frenkel pair (FP)
(FP > Eg and the recombination of relaxed (cold) electrons (e) and
holes (h) does not cause the creation of FPs. However, even these
oxides are insufficiently stable against radiation providing high
density of EEs. For example, irradiation of SiO2 by a powerful
6 keV-electron beam leads to the creation of radiation defects at 8 K
[11, 69]. It has been proposed that the effect is caused by a complex
structure of v-band of SiO2. Measuring the spectra of fast (subnanosecond) hole intraband luminescence (h-IBL) it was shown that,
in contrast to MgO, crystalline and amorphous quartz possesses a
wide v-band divided into subbands separated by the energy gap of
~1.5 eV. This gap impedes the relaxation of the holes, formed at the
irradiation in a lower subband, and facilitates the efficient hot e-h
recombination resulting in the energy release higher than (FP. A
similar energy gap inside the v-band was revealed in K2SO4 and
Scientific Report • 117
Rb2SO4 crystals, while it is absent in more radiation resistant (among
other sulphates) CaSO4 crystal [101, 208].
According to our experiments, the efficiency of hot recombination
can be drastically decreased in MgO crystals (samples were grown at
the Institute) with a continuous v-band (without splitting) at the
expense of the direct excitation of luminescent Cr3+ impurity ions by
hot electrons. A further experimental and theoretical study of this
mechanism of “luminescent protection” against radiation defect creation at e-h recombination lies ahead.
Comparative study of MgO and SiO2 crystals possessing wide
v-bands with different structure (continuous in MgO or split into two
subbands in D-quartz) has been started. The irradiation of these two
materials by 238U swift ions (kinetic energy of 2.5 GeV, fluence
1012 ions/cm2), i.e. under the same conditions of extremely high mean
energy loss leads to rather different results. MgO crystals demonstrate
significantly higher radiation resistance and hold their initial crystalline structure in spite of high concentration of F and F+ centres.
On the other hand, there is a layering in the region of SiO2 that
coincides with the range of uranium ions. A comparison of the
radiation effects in ion-irradiated pure and doped MgO single crystals
(grown at the Institute) with those under irradiation by fast neutrons
(fluences between 106 and 3u1011 n/cm2, Ural State Technical University) has been started as well. Fast neutrons efficiently create F+
centres with appropriate absorption band of and high-temperature
TSL peaks at 630 and 725 K.
The localization of holes in the single crystals MgO:Be MgO:Ca,
grown in IPUT, was investigated. In MgO, where a self-trapping of
holes has not been detected, the holes trapped by the isoelectronic
impurities are the closest analogue of self-trapped holes. As a result of
optical, thermoactivation and EPR measurements, the optical characteristics and delocalization temperature of the holes, trapped by Be
and Ca impurities, were determined. By EPR method, the structure
of the center, created at the localization of a hole by a Be2+ centre and
118 • Biannual Report 2004/2005
the spin-relaxation parameters, characterising the interaction between
the hole and the crystal lattice, were determined. It was found that
the Be ion in a cation site acts as a trapping center for both electrons
and holes. [13, 141, 149]
Pure and doped with germanium or oxygen thermally stable
Li4SO4 ceramics, considered as promising blanket materials for fusion
reactors, were synthesized. Electron-hole and interstitial-vacancy
processes have been investigated for the first time at 5–200 K in
highly pure Li4SO4 ceramics irradiated by electrons or 4–30 eV
photons. Low-temperature thermally stimulated luminescence (TSL)
as well as photostimulated luminescence (PSL) of ~2 V were detected. The regions of fundamental and defect-related regions were
separated measuring the creation spectra of TSL peaks and PSL.
Luminescent methods allow to perform comparative testing of Li4SO4
ceramics prepared by different technologies. [234]
Decay of a cation exciton with the formation
of an anion exciton in LiF
A short-wavelength analogue of the Raman effect, when excitons act
as phonons at the scattering of X-rays, was theoretically considered by
Agranovich and Ginzburg back in 1961. Previously we experimentally revealed the decay of a cation exciton (Ec # 34 V) into one
anion exciton (Ea # 8 and 7 V, respectively) and several e-h pairs in
NaCl and NaBr crystals. In 2005 the decay process of a cation
exciton with the formation of an anion one was revealed and
thoroughly studied in a LiF crystal (Ec # 62 V, Ea # 13 V) at
4.2–200 K. This important result is considered in details in research
highlights on pp. 39–41. Here we will only point out that this effect
should be searched for in lithium-containing dielectrics – promising
blanket materials for thermonuclear energetics. Using a complex of
thermoactivation spectroscopy methods, model LiF crystals have been
studied for the first time in a wide temperature region from 2.5 to
800 K (see also [78, 222]).
Scientific Report • 119
Decay of anion excitons into F-H pairs in LiF crystals
The e-h processes in tissue-equivalent LiF crystals doped with
magnesium and titanium are usefully employed for personal
J-dosimetry. However, these systems still turned out to be unsuitable
for the selective detection of fast neutrons. The peculiarity of anion
exciton decay into an FP in LiF, 1aF and NaCl crystals lies in the
fact that an H center, formed simultaneously with an F center, is
oriented along <111> directions, while in other alkali halides H
interstitials are oriented along <110> closely-packed anion rows and
the crowdion mechanism even at 5 K facilitates spatial separation of
defects and formation of stable F-H pairs. In LiF, the crowdion
motion of H interstitials is impossible and mainly short-lived (< 10 s)
F-H pairs are formed by X-irradiation at 5 K. Additional heating up
to 40–60 K is needed for defect separation inside FPs. [78, 222]
In collaboration with German colleagues from GSI (Darmstadt) it
was shown that the irradiation of LiF crystals by heavy swift ions or
D-particles causes a local heating in ion tracks sufficient for the
transformation of F-H pairs into more thermally stable – and –VK
pairs. In nominally pure and doped with various impurities LiF
crystals, such kind of irradiation at room temperature leads to the
formation of more complex defect associations, part of which remains
stable even at T > 600 K (TSL peaks at 650 and 740 K, heating rate
of 2.86 K/s). The intensity of these high-temperature TSL peaks in
LiF crystals ion-irradiated under the conditions of high excitation
density is significantly higher than in the case of X- or
VUV-irradiation. At the same time, local heating along ion tracks
(with radius up to 15 nm) suppresses the dosimetric TSL peaks at
450–500 K. [251]
120 • Biannual Report 2004/2005
Solid-state spectral transformers and
secondary electron emitters for PDPs
In recent years many dozens of dielectric materials with different
function mechanisms were tested in many laboratories of research
institutes and companies as spectral transformers of resonant xenon
discharge emission (hQ = 8.43 eV) into blue, green and red light in
plasma display panels. A dozen phosphors with a quantum yield of
QY = 0.8–1.0 at hQ = 8.43 eV has been found, but neither of them
possesses a sufficient radiation resistance. In addition, because of low
values of the receptivity constants for red elements of a human eye,
the use of existing efficient green phosphors requires the red emitters
with QY > 1. Widely used blue phosphor BaMgAl10O17:Eu2+
(BAM:Eu2+) as well several its modifications – BAM:Mn2+,
SrMgAl10O17:Eu2+ (SAM:Eu2+), BaMgAl14O23:Eu2+ have been
synthesized at the Institute and thoroughly studied in a wide region
of exciting photons of 5–30 eV. In a classic BAM:Eu2+ phosphor
(QY = 0.95r0.05 at hQ = 8.43 eV) the value of QY > 1 has been
detected in the spectral region of 12–20 eV. This revealed new “hole”
mechanism of photon multiplication (photon cutting) is connected
with the transfer of the energy excess of hot holes to luminescent Eu2+
ions. Several other e-h and excitonic mechanisms of photon multiplication have been considered as well. Unfortunately, the spectral
transformers for xenon discharge emission with real values of QY > 1
have not been elaborated yet. In 2005 a number of red phosphors (a
search for them is especially urgent at the present time) based on
YO2S:Eu3+ and several complex borates have been tested at the
Institute. [44, 162, 185, 252]
Very important issue for the development of PDPs is a further
improvement of a dielectric layer, which should provide efficient
emission of secondary electrons determining the operating voltage of
PDP. Such task is complicated while the dielectric layer also protects
electrodes from damage by energetic ions created in gas discharge.
According to the contract with SAMSUNG SDI, cathodo-
Scientific Report • 121
luminescence spectroscopy was applied for the investigation of MgO
films in an effort to compare their electronic properties with those for
single crystals. Another contract is dedicated for the elaboration of
new dielectric materials, which performance is expected to be better
than of the layers presently used in commercially available TV sets.
Physical processes in tungstates and other scintillators
Spectroscopic study of various scintillation materials for high-energy
physics and medical imaging systems was carried out. Luminescence
and defects creation processes were studied at 0.4–300 K for many
undoped and doped PbWO4 crystals with different concentrations of
various impurity and intrinsic defects, grown by different methods
and annealed at different conditions. Complex structure of the blue
WO42––related and green MoO42––related emission bands was found
and their origin established. For the first time, various localized
exciton states were identified. Photo/thermally stimulated decay of
the self-trapped and localized excitons and defect-related states into
stable defects was systematically studied and the corresponding
activation energies calculated. Luminescence thermal quenching was
explained by the decay of the corresponding exciton- or defect-related
state. [8, 10, 64, 139, 175]
Luminescence and defects creation processes were studied for the
undoped and Ce3+-doped single crystals of yttrium-aluminium and
lutetium-aluminium garnets and perovskites under selective excitation
in the 3.5–11.5 eV energy range. Luminescence characteristics of the
self-trapped excitons and the excitons localized near antisite defects
(YAl3+ and LuAl3+) and impurity ions were identified. It was found that
the antisite defects compete with Ce3+ ions in the processes of energy
transfer from the host lattice and negatively influence the decay
kinetics and light yield of these materials. For the first time the characteristics of Pr3+-doped garnets were determined. It was found that
this fast and effective scintillation material could successfully replace
122 • Biannual Report 2004/2005
Ce3+-doped crystals in some applications. [9, 64, 136, 138, 174, 189,
230, 231]
To understand charge-transfer processes in the scintillation
materials studied, simple model systems of two types were studied:
the crystals containing effective traps for electrons (e.g., CsBr:Tl ) and
the crystals without such traps (e.g., KI:Eu). As a result of charge
transfer, the localized exciton state is created in the former case. The
self-trapped exciton emission and exciton decay into F-H -type
defects were observed in the latter case. [130, 223]
Particular emphasis was put on the separation of excitonic and e-h
processes in crystals with different cations (Ca, Cd, Zn, Al) and
oxyanions (WO4, MoO4, SO4). The e-h processes were studied
mainly by means of recombination luminescence. The nature of
recombination luminescence was studied in detail in pure and doped
ZnWO4 crystals. A self-trapped hole was shown to be the main partner in both, thermally induced and photostimulated recombinations.
It was shown that in crystals characterized by a strong covalent
bonding in oxyanions, only Frenkel excitons are created close to the
bottom of the conduction band due to the transitions within the
oxyanionic states, while free electrons and holes are created 1–4 eV
above the fundamental absorption edge. In CaSO4, e-h pairs are
created even due to the lowest-energy transitions between the states of
SO4 complexes. The processes of energy transport between the host
lattice and impurity centres were studied in several crystals
(CaWO4:Bi, ZnWO4:Fe,Mo, Al2(WO4)3:Eu). The nature of the
relaxed excited state was determined by the methods of polarized
time-resolved spectroscopy in pure and doped CaWO4 and ZnWO4
crystals. The triplet states of unperturbed or impurity perturbed
oxyanionic (WO4, MoO4) excitons were shown to be responsible for
the main emission bands in these crystals. The study was performed
in collaboration with Hungarian, Latvian, Dutch and Swedish
scientists. [36, 46, 87, 172, 188, 233, 235]
Scientific Report • 123
Diagnostics of novel insulator materials using
luminescence spectroscopy
VUV spectroscopy was applied in studies of several thin oxide films
(HfO2, ZrO2, Al2O3) prepared by atomic layer deposition methods.
Such films have a great potential for technological applications as
novel insulator layers in electronics and as converters of ionizing
radiation in X-ray microtomography devices. It was shown that the
intrinsic emission is due to the radiative decay of self-trapped excitons
(STEs). Also the energetic parameters as the energy gap, lifetime of
STEs, etc. of substances in different crystallographic modifications
were determined. [3, 159, 162, 183, 225, 244]
Systematic investigation of energy transfer processes was carried
out for Eu doped LiCaAlF6 and LiSrAlF6 crystals, which have
potential applications in lightening (Eu2+ emits in blue and Eu3+ in
red), scintillation as well as in dosimetry. It was established that
during the crystal growth Eu ions enter into LiCaAlF6 lattice in biand trivalent state resulting in the emissions due to the 5d o 4f
(a370 nm) and 4f o 4f (a590 nm) transitions. The 4f emissions of
Eu3+ ions are efficiently excited through the 4f o 4f, F– o Eu3+
charge transfer transitions and the excitonic states localized near
impurity. The yield of the 5d o 4f emission of Eu2+ is high in
the intra-center excitation and is considerably less in the host
absorption limiting their performance for scintillation purposes. [161,
245].
Using a novel light source, the free electron laser built up at DESY
(Hamburg, Germany), which provides up to 1013 VUV photons in
the ultrashort ( < 50 fs ) pulse, the excitation density effects on the
relaxation of electronic excitations in BaF2 and YAG:Ce crystals were
investigated. The increased excitation density led to the remarkable
shortening of luminescence decays in both crystals. There are several
mechanisms (e.g., interaction of spatially close excitations, local
heating of crystal, excited state absorption) causing such drastic
124 • Biannual Report 2004/2005
changes in the relaxation dynamics in comparison with effects
observed under the excitation by conventional light sources. [160]
Compiled by Aleksandr Lushchik
Resonant X-ray scattering (RIXS) studies
The excitation-decay processes at the F 1s photoabsorption edge in
LiF crystal are studied using resonant inelastic x-ray scattering
spectroscopy (RIXS). The Raman-type linear dispersion and the
narrowing of the x-ray fluorescence peak are observed at resonant
excitation. A theoretical model based on the Kramers-Heisenberg
formula describes well the main features in fluorescence spectra and
allows one to separate the contributions of the exciton and the
conduction states in the scattering spectra. At the same time, the role
of the shape of the spectral distribution within the incident radiation
is emphasized as being critically sensitive to the number, kind, and
onset of the spectral features, which finally appear in the scattering
spectra at a particular incident photon energy, particularly in the
subthreshold excitation region. Contrary to case of LiF, core excitons
were not identified in O 1s photoabsorption edge of MgO as the
narrowing of the X-ray fluorescence peak was not observed. New
types of states in LiCl, where both Li core electrons are excited, have
been observed in RIXS. States with one, as well as both, of the excited
electrons localized at the site of the bare Li nucleus are identified. The
results add a dimension to the hypersatellite concept in x-ray
emission, and demonstrate that resonant spectroscopy involving
multiple core vacancies provides information about decay dynamics,
electron correlation, and chemical environment. [7, 28, 156]
Scientific Report • 125
Studies of fullerenes
Vibronic coupling in solid C60 has been investigated with a combination of resonant photoemission spectroscopy (RPES) and RIXS.
Excitation as a function of energy within the lowest unoccupied
molecular orbital resonance yielded strong oscillations in intensity
and dispersion in RPES, and a strong inelastic component in RIXS.
Reconciling these two observations establishes that vibronic coupling
in this core hole excitation leads to predominantly inelastic scattering
and localization of the excited vibrations on the molecule on a
femtosecond time scale. The coupling extends throughout the widths
of the frontier valence bands. The significant angle-dependence in the
core level and valence line shapes of photoelectron spectra of single
crystal K3C60 has been detected. This allowed the identification of
bulk and surface components in the data, and allows us to explain the
anomalous line shapes observed for this system. The states near the
Fermi level are associated with the bulk of the sample. There is strong
evidence of an insulating surface layer, which we ascribe to intermolecular electron correlations. These results simplify the interpretation of previous, apparently conflicting observations. [165, 209]
Photoelectron spectroscopy of thin insulating films
Solid-state effects in the creation and decay of K 2p core excitations
in thin KF films on Cu(100) surface have been studied in resonant
Auger spectra, excited using synchrotron radiation. The spectra of
films of various thickness starting from a single monolayer were
measured. The photoabsorption spectra reveal crystal field splitting
already at film thickness of about 1 monolayer. The Auger decay
spectra of the K 2p–13d core excitations in films of thickness up to
2 monolayers exhibit a band characteristic of the decay of core ionised
states, showing that the excited electron delocalises into substrate
before the core hole decays. In thicker films the coexistence of the
decay of excited states in the bulk of the KF crystalline film and of
126 • Biannual Report 2004/2005
ionised states at the KF–metal interface is observed, indicating that
the charge transfer probability from the upper layers of the film into
the metallic substrate is strongly reduced. Photoelectron spectroscopy
has been used for the studies of HfO2 films, prepared by atomic layer
deposition from HfCl4 and H2O on Si(100) in the temperature range
of 300–600°C. At low temperatures, films grow faster and are structurally more disordered, compared to films grown at high temperatures. At high temperatures, the films are better crystallized, but grow
slower and contain grain boundaries extending from substrate to gate
electrode. [157, 180]
Time-of-flight and photoelectron spectroscopy
of molecules of alkali halides
Photoionisation and photofragmentation of molecular rubidium
halides following photoexcitation in the vacuum ultraviolet region are
investigated by using time-of-flight mass spectroscopy and photoelectron spectroscopy. For this purpose total and partial ion yield
spectra are measured from the vapours of RbF, RbCl, RbBr and RbI.
Two different decay channels – spectator and participator type – are
studied in different rubidium halide molecules. It is demonstrated
that the opening of the spectator channel takes place at different
excitation energies, depending on the halide atom in the molecule.
[164] Photoelectron spectra excited at resonances and between
resonances are measured as well. Although all studied molecules have
very similar electronstructure, photoelectron spectra show up remarkable difference. This can be explained according to the model,
where the ratio between nuclear vibrational period and the electronic
decay lifetime play a decisive role. [164, 232]
Absorption spectra of CsCl molecule and dimer were measured by
using time-of-flight technique in the photon energy region of 5p
excitations of Cs. The experimental spectra was analyzed by means of
point-charge-molecular-field model, which is based on the exact
multiple expansion of electrostatic field induced by the ligands
Scientific Report • 127
assumed to be point charges and use a complete set of LSJM- states in
diagonalization. The calculations show strong inter-configuration
mixing between the states originated from the excited 5p55d and
5p56s configurations. A good accordance between the measured and
theoretical spectra shows that proposed calculation model provide a
good base for the interpretation of the lowest excitations of the
molecules with ionic bonding. [204]
Compiled by Arvo Kikas
5. PUBLICATIONS
PAPERS 2004
1. J. Aarik, A. Aidla, A. Kikas , T. Käämbre, R. Rammula, P. Ritslaid,
T. Uustare, V. Sammelselg, “Effects of precursors on nucleation in
atomic layer deposition of HfO2,” Appl. Surf. Sci., 230, pp. 292–300,
2004.
2. J. Aarik, V. Bichevin, I. Jõgi, H. Käämbre, M. Laan, V. Sammelselg,
“Fowler-Nordheim tunnelling in Au-TiO2-Ag film structures,” Central
European J. Phys., 2, pp. 147–159, 2004.
3. J. Aarik, H. Mändar, M. Kirm, L. Pung, “Optical characterization of
HfO2 thin films grown by atomic layer deposition,” Thin Solid Films,
466, pp. 41–47, 2004.
4. P. Adamson, “Reflection of light in a long-wavelength approximation
from a N-layer systm of inhomogeneous dielectric films and optical
diagnostics of ultrathin layers. II Transparent substrate,” J. Opt. Soc.
Am. B, 21, pp. 645–654, 2004.
5. P. Adamson, “High-aperture focusing systems: control of light
concentration in focal region by pupil filtering,” J. Modern Optics, 51,
No. 1, pp. 65–74, 2004.
6. P. Adamson, “Laser diagnostics of nanoscale dielectric films on transparent substrate by integrating differential reflectivity and ellipsometry,”
Optics & Laser Technology, 36, No. 8, pp. 661–668, 2004.
7. M. Agåker, J. Söderström, T. Käämbre, C. Glover, L. Gridneva,
T. Schmitt, A. Augustsson, M. Mattesini, R. Ahuja, J.-E. Rubensson,
“Resonant inelastic soft X-ray scattering at hollow lithium states in solid
LiCl,” Phys. Rev. Lett., 93, pp. 016404, 2004.
8. V. Babin, P. Bohacek, E. Bender, A. Krasnikov, E. Mihokova, M. Nikl,
N. Senguttuvan, A. Stolovits, Y. Usuki, S. Zazubovich, “Decay kinetics
of green emission in tungstates and molybdates,” Radiat. Measurements,
38, pp. 533–537, 2004.
Publications • 129
9. K. Blazek, A. Krasnikov, K. Nejezchleb, M. Nikl, T. Savikhina,
S. Zazubovich, “Luminescence and defects creation in Ce3+doped
Lu3Al5O12 crystals,” Phys. stat. sol. (b), 241, pp. 1134–1140, 2004.
10. P. Bohacek, N. Senguttuvan, V. Kiisk, A. Krasnikov, M. Nikl, I. Sildos,
Y. Usuki, S. Zazubovich, “Red emission of PbWO4 crystals,” Radiat.
Measurements, 38, pp. 623–626, 2004.
11. M. Cannas, S. Angello, F. M. Gelardi, R. Boscaino, A. N. Trukhin,
P. Liblik, Ch. Lushchik, M. F. Kink, Y. Maksimov, R. A. Kink,
“Luminescence of J-radiation induced defects in D-quartz,” J.Phys.:
Condens. Matter, 16, pp. 7931–7939, 2004.
12. D. Di Martino, A. Krasnikov, M. Nikl, A. Vedda, S. Zazubovich, “The
3.83 eV luminescence of Gd-enriched phosphate glasses,” Phys. stat. sol.
(a), 201, pp. R38–R40, 2004.
13. S. A. Dolgov, V. Isakhanyan, T. Kärner, P. Liblik, A. Maaroos,
S. Nakonechnyi, “Luminescence of [Be]+-centre in MgO:Be,” Radiat.
Measurements, 38, pp. 699–702, 2004.
14. S. Dueñas, H. Castán, H. Garc a, J. Barbolla, K. Kukli, J. Aarik, “Effect
of growth temperature and postmetallization annealing on the interface
and dielectric quality of atomic layer deposited HfO2 on p and n
silicon,” J. Appl. Phys., 96, pp. 1365–1372, 2004.
15. S. Dueñas, H. Castán, H. Garc a, J. Barbolla, K. Kukli, J. Aarik,
A. Aidla, “The electrical-interface quality of as-grown atomic-layerdeposited disordered HfO2 on p- and n-type silicon,” Semicond. Sci.
Technol., 19, pp. 1141–1148, 2004.
16. A. Ellervee, J. Linnanto, A. Freiberg, “Spectroscopic and quantum
chemical study of pressure effects on solvated chlorophyll,” Chem.Phys.
Lett., 394, pp. 80–84, 2004.
17. M. Faarinen, S. Bazhal, U. Falkengren-Grerup, R. Hellborg, M. Kiisk,
C.E. Magnusson, P. Persson, G. Skog, K. Stenström, “26Al at the AMS
facility in Lund,” Nucl. Instr. and Meth., Elsevier, London, B223–224,
No. August, pp. 130–134, 2004.
18. V. Fedossejev, “Pecluriarities of the reflection of light beam with optical
voticies,” Proc. SPIE, 5481, pp. 154–159, 2004.
19. A. Freiberg, M. Rätsep, K. Timpmann, G. Trinkunas, “Dual fluorescence of single LH2 antenna nanorings ,” J. Lumin., 108, pp. 107–
110, 2004.
130 • Biannual Report 2004/2005
20. M. Friedrich, W. Pilz, N. Bekris, M. Glugla, M. Kiisk, V. Liechtenstein,
“A small and compact AMS facility for tritium depth profiling,” Nucl.
Instr. Meth., Elsevier, London, B223–224, pp. 21–25, 2004.
21. A. Gall, A. Ellervee, B. Robert, A. Freiberg, “The effect of internal voids
in membrane proteins: high pressure study of two membrane proteins
from Rhodobacter sphaeroides,” FEBS Letters, 560, pp. 221–225, 2004.
22. V. Hizhnyakov, V. Boltrushko, H. Kaasik, I. Sildos, “Phase relaxation
in the vicinity of the dynamic instability: anomalous temperature
dependence of zero-phonon line,” J. Lumin., 107, pp. 351–358, 2004.
23. V. Hizhnyakov, J. Kikas, J. Takahashi, A. Laisaar, A. Suisalu, An. Kuznetsov, “Two-level systems in glasses under high pressure : temperature
cycling effect,” Phys. stat. sol. (c), 1, No. 11, pp. 2937–2940, 2004.
24. V. Hizhnyakov, G. Benedek, “Quantum diffusion: effects of local
distortion of phonons,” Phys. stat. sol. (c), 1, pp. 3019–3022, 2004.
25. I. Jõgi, J. Aarik, V. Bichevin, H. Käämbre, M. Laan, V. Sammelselg,
“Fowler-Nordheim tunnelling in TiO2 films grown by atomic layer
deposition on gold substrates,” Proc. Estonian Acad. Sci. Phys. Math.,
53, pp. 226–236, 2004.
26. M. Kiisk, R. Hellborg, P. Persson, M. Faarinen, G. Skog, K. Stenström,
“The charge state distribution of Be, C, Cl and Al ions at the Lund
Pelletron accelerator with the recently modified terminal pumping in
use,” Nucl. Instr. and Meth., Elsevier, London, A521, No. April,
pp. 299–305, 2004.
27. V. Kiisk, I. Sildos, O. Sild, J. Aarik, “The influence of a waveguiding
structure on the excitonic luminescence of anatase thin films,” Opt.
Materials, 27, pp. 115–118, 2004.
28. A. Kikas, T. Käämbre, A. Saar, K. Kooser, E. Nõmmiste, I. Martinson,
V. Kimberg, S. Polyutov, F. Gel’mukhanov, “Resonant inelastic X-ray
scattering at the F 1s photoabsorption edge in LiF. Interplay of excitonic
and conduction states, and Stokes’ doubling,” Phys. Rev. B, 70, No. 8,
pp. 085102, 2004.
29. A. Kikas, T. Käämbre, A. Saar, K. Kooser, E. Nõmmiste, I. Martinson,
V. Kimberg, S. Polyutov, F. Gel’mukhanov, “Erratum: Resonant
inelastic X-ray scattering at the F 1s photoabsorption edge in LiF.
Interplay of excitonic and conduction states, and Stokes’ doubling
(Phys. Rev. B 70, 085102, 2004),” Phys. Rev. B, 70, No. 20,
pp. 209902, 2004.
Publications • 131
30. I. Kink, V. Kisand, K. Saal, T. Tätte, M. Lobjakas, A. Lõhmus, “Laser
ablation for 3D nanometric imaging of solids,” Proc. Estonian Acad.
Sci. Eng., 10, No. 1, pp. 30–38, 2004.
31. V. Kisand, E. Kukk, M. Huttula, A. Koivukangas, H. Aksela,
E. Nõmmiste, S. Aksela, “Corrigendum: Fragmentation and electronic
decay of vacuum ultraviolet-excited resonant states of molecular CsCl,”
J. Phys. B: At. Mol. Opt. Phys., 37, pp. 3011, 2004.
32. P. Konsin, B. Sorkin, “Influence of external fields on the properties of
SrTi(16O1–x18Ox)3 at oxygen isotope substitution,” Ferroelectrics, 308,
pp. 33–37, 2004.
33. P. Konsin, B. Sorkin, “A generalized two-band model for the superconductivity in MgB2,” Supercond. Sci. Technol. 17, pp. 1472–1476,
2004.
34. M. M. Korshunov, S. G. Ovchinnikov, A. V. Sherman, “Spin fluctuations influence on quasiparticle spectrum of realistic p-d model,”
J. Magn. and Magnetic Materials, 272–276, pp. e575–e577, 2004.
35. M. M. Korshunov, S. G. Ovchinnikov, A. V. Sherman, “Effective
Hamiltonian and properties of the normal and superconducting phases
of n-type cuprates,” JETP Letters, 80, No. 1, pp. 39–43, 2004.
36. A. Kotlov, L. Jönsson, M. Kirm, A. Lushchik, V. Nagirnyi, E. Rivkin,
A. Watterich, B. I. Zadneprovski, “Luminescence study of self-trapped
holes in pure and Fe or Mo doped ZnWO4 crystals,” Radiat. Measurements, 38, pp. 715–718, 2004.
37. N. Kristoffel, P. Rubin, “Superconducting gaps and pseudogaps in a
composite model of two-component cuprate,” Physica C, 402, pp. 257–
262, 2004.
38. N. Kristoffel, P. Rubin, “Effect of photodoping on cuprate superconductivity,” Physica C, 418, pp. 49–52, 2004.
39. K. Kukli, J. Aarik, M. Ritala, T. Uustare, T. Sajavaara, J. Lu, J. Sundqvist, A. Aidla, L. Pung, A. Hårsta, M. Leskelä, “Effect of selected
atomic layer deposition parameters on the structure and dielectric
properties of hafnium oxide films,” J. Appl. Phys., 96, pp. 5298–5307,
2004.
40. P. Kuusk, M. Saal, “A cosmological model of holographic brane
gravity,” Gen. Rel. Gravit., 36, No. 5, pp. 1001–1014, 2004.
132 • Biannual Report 2004/2005
41. S. Lange, I. Sildos, V. Kiisk, J. Aarik, “Energy transfer in the photoexcitation of Sm3+ implanted TiO2 thin films,” Mat. Sci. Engineer. B,
112, pp. 87–90, 2004.
42. R.-K. Loide, I. Ots, R. Saar, P. Suurvarik, “On superfield equations of
motion,” Hadronic J., 27, pp. 151–163, 2004.
43. J. Lu, J. Sundqvist, M. Ottosson, A. Tarre, A. Rosental, J. Aarik,
A. Hårsta, “Microstructure Characterisation of ALD-grown epitaxial
SnO2 thin films,” J. Crystal Growth, 260, pp. 191–204, 2004.
44. A. Lushchik, Ch. Lushchik, A. Kotlov, I. Kudryavtseva, A. Maaroos,
V. Nagirnyi, E. Vasil’chenko, “Spectral transformers of VUV radiation
on the basis of wide-gap oxides,” Radiat. Measurements, 38, pp. 747–
752, 2004.
45. K. Mauring, V. Novoderezhkin, A. Taisova, G. Fetisova, “The model of
pigmental aggregation in the chlorosomal antenna of the green
bacterium Chloroflexus Aurantiacus,” Molec. Biol., 38, No. 2, pp. 266–
271, 2004.
46. V. Nagirnyi, L. Jönsson, M. Kirm, A. Kotlov, A. Lushchik, I. Martinson, A. Watterich, B. I. Zadneprovski, “Luminescence study of pure and
Fe or Mo doped ZnWO4 crystals,” Radiat. Measurements, 38, pp. 519–
522, 2004.
47. I. Ots, H. Uibo, H. Liivat, R.-K. Loide, “Possible anomalous ZZ and
Z couplings and Z boson spin orientation in e+e– oZ ,” Nucl. Phys. B,
702, pp. 346–356, 2004.
48. V. Palm, M. Pärs, J. Kikas, “Hole burning and single-molecule spectroscopy of terrylene in incommensurate biphenyl,” J. Lumin., 107, pp. 57–
61, 2004.
49. A. V. Pokropivny, D. Erts, V. V. Pokropivny, A. Lõhmus, R. Lõhmus,
H. Olin, “Study of nanoscale contacts with the help of combined
TEM-AFM technique and theoretical MD-TM calculations: in situ
transformations of gold nanowires,” Phys. Low-Dimens. Struct.,
No. 1/2, pp. 83–90, 2004.
50. I. Rebane, “Differences of the radiative linewidth in single-impurity
molecule spectroscopy,” J. Lumin., 107, pp. 38–41, 2004.
51. Karl K. Rebane, “Purely electronic zero phonon lines. Recent
developments,” J. Lumin., 107, pp. 122–128, 2004.
Publications • 133
52. K. Reivelt, P. Saari, “The Bessel-Gauss pulse as an appropriate mathematical model for optically realizable localized waves,” Opt. Lett., 29,
No. 11, pp. 1176–1178, 2004.
53. I. Renge, “Lennard-Jones model of frequency-selective baro- and
thermochromism of spectral holes in glasses,” J. Phys. Chem., 108,
No. 29, pp. 10596–10606, 2004.
54. P. Rubin, A. Sherman, “Magnetic properties of the two-dimensional
Heisenberg model on a triangular lattice,” Phys. Lett. A, 334, No. 4,
pp. 312–316, 2004.
55. R. Ruus, K. Kooser, E. Nõmmiste, A. Saar, I. Martinson, A. Kikas,
“Potential barrier effects in Cs 3d resonance photoemission of CsF,”
J. Electron Spectrosc. Relat. Phenom., 137–140, pp. 377–381, 2004.
56. P. Saari, K. Reivelt, “Generation and classification of localized waves by
Lorentz transformations in Fourier space,” Phys. Rev. E, 69, No. 3,
pp. 036612, 1–12, 2004.
57. G. Seibold, F. Becca, P. Rubin, J. Lorenzana, “Time-dependent Gutzwiller theory of magnetic excitations in the Hubbard model,” Phys. Rev.
B, 69, No. 15, pp. 155113 (1–12), 2004.
58. A. Sherman, “Magnetic properties of underdoped cuprate perovskites ,”
Mol. Phys. Rep., 39, pp. 234–238, 2004.
59. A. Sherman, M. Schreiber, “Low-frequency incommensurate magnetic
response in strongly correlated systems,” Phys. Rev. B, 69, No. 10,
pp. 100505(R) 1–4, 2004.
60. A. Sherman, “Spectral and magnetic properties of the t-J model of
cuprate perovskites,” Phys. stat. sol. (b), 241, No. 9, pp. 2097–2108,
2004.
61. A. Sherman, “Evolution of the hole and spin-excitation spectra of the
two-dimensional t-J model: From light to heavy doping,” Phys. Rev. B,
70, No. 18, pp. 184512, 1–4, 2004.
62. I. Sildos, S. Lange, T. Tätte, V. Kiisk, M. Kirm, J. Aarik, “Emission of
rare earth ions incorporated into metal oxide thin films and fibres,”
Mater. Res. Soc. Proc., 796, pp. 70, 2004.
63. A. Suisalu, M. Jänes, J. Kikas, “Temperature transformation of dopant
spectra in incommensurate biphenyl,” J. Phys. Chem. B, 108, No. 29,
pp. 10404–10407, 2004.
134 • Biannual Report 2004/2005
64. S. Zazubovich, “New scintillation materials for scientific, medical and
industrial applications,” Proc. Estonian Acad. Sci. Phys. Math. , 53,
No. 4, pp. 237–251, 2004.
65. I. Tehver, “A possibility of distinguishing the inhomogeneous broadening via coherent Raman spectra,” J. Lumin., 107, pp. 266–270,
2004.
66. I. Tehver, “Calculation of CARS excitation profile of ZnPc,” Phys. stat.
sol. (c), 1, No. 11, pp. 3154–3157, 2004.
67. K. Timpmann, G. Trinkunas, J. D. Olsen, C. N. Hunter, A. Freiberg,
“Bandwidth of excitons in LH2 bacterial antenna chromoproteins,”
Chem.Phys. Lett., 398, pp. 384–388, 2004.
68. K. Timpmann, M. Rätsep, C. N. Hunter, A. Freiberg, “Emitting
exciton polaron states in core LH1 and peripheral LH2 bacterial lightharvesting complexes,” J. Phys. Chem. B, 108, pp. 10581–10588, 2004.
69. A. Trukhin, P. Liblik, Ch. Lushchik, J. Jansons, “UV cathodoluminescence of crystalline D-quartz at low temperatures,” J. Lumin., 109,
pp. 103–109, 2004.
70. A. N. Trukhin, M. F. Kink, Yu. A. Maksimov, R. A. Kink, T. A. Ermolenko, I. I. Cheremisin, “Luminescence of fluorine-doped and nondoped silica glass excited with an ArF laser,” J. Non-Cryst. Solids, 342,
pp. 25–31, 2004.
PROCEEDINGS 2004
71. J. Aarik, “Elektroonikamaterjalide tehnoloogia arengu probleemidest ja
perspektiividest,” In: Eesti Teaduste Akadeemia Seminari Materjalid,
Teaduse uued suunad, Materjaliteadus, Eesti Teaduste Akadeemia,
Tallinn, pp. 23-30, 2004.
72. P. Adamson, “Reflection characteristics of nanoscopic layered
structures and optical diagnostics of ultrathin dielectric films,” In:
Proc. 2003 Third IEEE Conference on Nanotechnology. IEEENANO 2003 (Cat. No.03TH8700). Piscataway, NJ, USA, IEEE, 2,
pp. 836–839, 2003.
73. P. Adamson, “Optical diagnostics of nanometer dielectric films by
combining ellipsometry and differential reflectance,” In: Physics,
Chemistry and Application of Nanostructures (Eds. V. E. Borisenko,
Publications • 135
74.
75.
76.
77.
78.
79.
80.
81.
S. V. Gaponenko, and V. S. Gurin), World Scientific, Singapore,
pp. 96–99, 2003.
P. Adamson, “Optical probing of nanoscopic insulating layered
structures via differential characteristics of specular reflection of light ,”
In: IEEE Proc. 2004 International Conference on MEMS, NANO and
Smart Systems (Cat. #P2189). USA, IEEE, pp. 535–541, 2004.
M. Agåker, J. Söderström, T. Käämbre, C. Glover, L. Gridneva,
T. Schmitt, A. Augustsson, M. Mattesini, R. Ahuja, J. E. Rubensson,
“Resonant inelastic soft X-ray scattering at hollow lithium states in
solids,” In: Program and Abstracts, The 14th Intern. Conf. on Vacuum
Ultraviolet Radiation Physics, Cairns, Australia, pp. 37, 2004.
A. Agui, S. Butorin, T. Käämbre, C. Såthe, T. Saitoh, Y. Moritomo,
J. Nordgren, “Resonant O Ka Emission Spectroscopy of double layered
Manganite La1.2Sr1.8Mn2O7,” In: Program and Abstracts, The 14th
Intern. Conf. on Vacuum Ultraviolet Radiation Physics, Cairns,
Australia, pp. 96, 2004.
V. Fedossejev, “A new nonspecular effect in reflection of a light beam
carrying orbital angular momentum,” In: Biannual Report 2002/2003,
Institute of Physics, University of Tartu, ISSN 1406–7927, Tartu,
pp. 40–43, 2004.
E. Feldbach, I. Kudryavtseva, A. Lushchik, Ch. Lushchik, I. Martinson, V. Nagirnyi, E. Vasil’chenko, “Creation and transformation of
defects by VUV radiation in LiF single crystals,” In: MAX-LAB
Activity Report 2003, National Laboratory, Lund, Sweden, pp. 124–
125, 2004.
A. Freiberg, “What is the bandwidth of excitons in photosynthetic
antenna nanoaggregates,” Biannual Report 2002/2003, Institute of
Physics, University of Tartu, ISSN 1406–7927, Tartu, pp. 51–53,
2004.
C. Glover, M. Agåker, T. Käämbre, T. Schmitt, M. Adell, L. Ilver,
J. Kanski, L. Kjeldgaard, J. E. Rubensson, “Localized 3d excitations in
Ge, GaAs, and GaN, populated in inelastic soft X-ray scattering,
resonantly enhanced at the 3p edges,” In: Program and Abstracts, The
14th Intern. Conf. on Vacuum Ultraviolet Radiation Physics, Cairns,
Australia, pp. 119, 2004.
C. Glover, T. Käämbre, M. Agaker, L. Gridneva, T. Balasubramanian,
J. Andersen, J. E. Rubensson, “Effects of momentum conservation in
136 • Biannual Report 2004/2005
82.
83.
84.
85.
86.
87.
88.
89.
90.
91.
92.
resonant inelastic soft X-ray scattering in the bulk and at the surface of
Be metal,” In: Program and Abstracts, The 14th Intern. Conf. on
Vacuum Ultraviolet Radiation Physics, Cairns, Australia, pp. 232,
2004.
M. Haas, “Coherent resonant scattering of synchrotron radiation in
randomly oriented paramagnetic and diamagnetic biomolecular 57Fe
complexes,” In: Biannual Report 2002/2003, Institute of Physics,
University of Tartu, ISSN 1406–7927, Tartu, pp. 30–35, 2004.
R. Jaaniso, “Milline oli aasta 2003 füüsikas ja Eesti füüsikas?” In: Eesti
Füüsika Seltsi Aastaraamat 2003, Tartu, pp. 5–8, 2004.
A. Kikas, T. Käämbre, A. Saar, K. Kooser, E. Nõmmiste, I. Martinson, “Resonant Inelastic X-ray Scattering at the K edge of oxygen and
fuorine in insulators,” In: Program and Abstracts, The 14th Intern.
Conf. on Vacuum Ultraviolet Radiation Physics, Cairns, Australia,
pp. 231, 2004.
A. Kikas, “Röntgenkiirguse Ramani hajumine,” In: Eesti Füüsika Seltsi
aastaraamat 2003, Tartu, Eesti, pp. 50, 2004.
V. Kisand, E. Nõmmiste, E. Kukk, A. Caló, H. Aksela, S. Aksela,
“Photoexcitation, photoionisation and photofragmentation of molecular rubidium halides,” In: MAX-LAB Activity Report 2003, National
Laboratory, Lund, Sweden, pp. 126–127, 2004.
A. Kotlov, S. Dolgov, L. Jönsson, A. Lushchik, V. Nagirnyi, G. Svensson, B. I. Zadneprovski, “Excitonic and recombination luminescence
of Al2(WO4)3 crystals,” In: MAX-LAB Activity Report 2003, National
Laboratory, Lund, Sweden, pp. 128–129, 2004.
N. Kristoffel, P. Rubin, “Kupraatülijuhtide energeetilised karakteristikud ja nende seosed dopeeringskaalal,” In: Eesti Füüsika Seltsi
aastaraamat 2003, Tartu, pp. 50–51, 2004.
N. Kristoffel, P. Rubin, “Two-component scenario and related gaps in
cuprates,” cond-mat/0408574, pp. 1–14, 2004.
N. Kristoffel, T. Örd, “Magneesiumdiboriidi ülijuhtivuse mehhanism,” In: Eesti Vabariigi Teaduspreemiad, pp. 26–35, 2004.
N. Kristoffel, T. Örd, “Magnesium diboride superconductivity,” In:
Biannual Report 2002/2003, FI, TÜ, pp. 35–40, 2004.
E. Kukk, M. Huttula, J. Rius i Riu, H. Aksela, S. Aksela, R. Ruus,
“VUV-induced processes in alkali halide dimer molecules – how well
does the ionic approach work?” In: Program and Abstracts, The 14th
Publications • 137
93.
94.
95.
96.
97.
98.
99.
100.
101.
102.
Intern. Conf. on Vacuum Ultraviolet Radiation Physics, Cairns,
Australia, pp. 54, 2004.
P. Kuusk, M. Saal, “Advances in string and brane cosmology,” In:
Biannual Report 2002/2003, Institute of Physics, University of Tartu,
ISSN 1406–7927, Tartu, pp. 44–47, 2004.
P. Kuusk, “Eesõna,” In: Eesti Füüsika Seltsi aastaraamat 2003, Tartu,
pp. 3, 2004.
H. Käämbre, H. Jõgi (compilers), “Biannual Report 2002/2003, Inst.
of Physics, Univ. of Tartu,” In: , Tartu, Estonia, pp. 1–205, 2004.
H. Käämbre (compiler), “Institute of Physics of the University of
Tartu,” In: Centres of Excellence of Estonian Science, Association of
the Centres of Excellence of Estonian Science, Tallinn, Estonia,
pp. 77–92, 2004.
E. Nõmmiste, V. Kisand, M. Valden, M. Hirsimäki, E. Kukk,
T. Käämbre R. Ruus, A. Kikas, “Studing KF monolayers on copper
substrate,” In: Book of Abstracts, Fifth Nordic Conf. on Surface
Science, Tampere, Finland, pp. 57, 2004.
E. Nõmmiste, V. Kisand, E. Kukk, A. Calo, H. Aksela, S. Aksela,
“Photoexcitation, -ionization and fragmentation of molecular rubidium halides,” In: Program and Abstracts, The 14th Intern. Conf. on
Vacuum Ultraviolet Radiation Physics, Cairns, Australia, pp. 133,
2004.
V. Peet, “Mittegaussilised laserkimbud mittelineaarses optikas,” In:
Eesti Füüsika Seltsi aastaraamat 2003, Tartu, pp. 13–27, 2004.
A. V. Pokropivny, R. Lõhmus, D. Erts, I. Hussainova, H. Olin,
A. Lõhmus, “Transformations of gold nanocontacts studied by molecular dynamics simulations,” In: Proceedings of NANOTECH 2004
Intern. Conf. on Nanotechnology, Boston, USA, pp. 1–5, 2004.
D. E. Rakhimov, F. A. Savikhin, A. Ch. Lushchik, “Intrinsic emissions
in alkali metal sulphates,” In: Proc. Intern. Conf. on Physico-Chemical
Processes in Inorganic Materials, Kemerovo, Russia, 1, pp. 80–81,
2004.
R. Rammula, J. Aarik, A. Kikas, T. Käämbre, V. Sammelselg, “AFM
and XPS studies of ultrathin HfO2 films prepared by ALD,” In: Proc.
5th Nordic-Baltic Scanning Probe Microscopy Workshop, 16–19 June,
2004, Trondheim, Norway (Eds. Th. Tybell, A. Borg), Visual
Knowledge AS, Trondheim, pp. 93–95, 2004.
138 • Biannual Report 2004/2005
103. E. Realo, K. Realo, “Natural radionuclides in radium-rich soils in
North-East Estonia,” In: The Natural Radiation Environment VII.
Book Series “Radioactivity in the Environment”. Simopoulos et al
(Eds.). ISBN: 0-08-044137-8, Elsevier, London, pp. 00–00, 2004.
104. K. Realo, R. Koch, M. Lust, A. Uljas, E. Realo , “Lead-210 in air and
surface soil in NE Estonia,” In: Full Papers of IRPA-11, 11th Int.
Congress of International Radiation Protection Association, 23–28
May 2004, Madrid, CD-ROM ja http://www.irpa11.com, SRPC,
Spain, 6a, No. 56, pp. 1–8, 2004.
105. V. Sammelselg, J. Aarik, A. Kikas, R. Rammula, T. Käämbre, K. Kooser, A. Zakharov, I. Martinson, “Study of growth process of ultrathin
hafnia films,” In: MAX-LAB Activity Report 2003, National Laboratory, Lund, Sweden, pp. 84–85, 2004.
106. J. Takahashi, A. Suisalu, An. Kuznetsov, A. Laisaar, V. Hizhnyakov,
J. Kikas, “Effect of hydrostatic pressure on irreversible thermal
transformations in a polymer glass at low temperatures,”
http://arXiv.org/abs/cond-mat/0401345, pp. 1–28, 2004.
POPULAR SCIENTIFIC ARTICLES, PUBLICISM 2004
107. J. L. Birman, A. A. Maradudin, R. Pick, K. K. Rebane, “Ija Pavlovna
Ipatova,” Physics Today, No. 8, pp. 69–70, 2004.
108. R. Koch, “Tartu rahu 84. aastapäeval,” Ajaleht “Rahvuslik Koguja”,
Tartu, Eesti, No. 1 (34), pp. 1, 2004.
109. P. Kuusk, “Bernard Bolzano ja matemaatika põhialused,” Akadeemia,
16, pp. 592–632, 2004.
110. P. Kuusk, “Bernard Bolzano “Lisandusi matemaatika põhjendatuma
esituse juurde” (valikuline tõlge),” Akadeemia, 16, pp. 567–591, 2004.
111. P. Kuusk, “Kihlveod mustade ja valgete aukude ümber,” Horisont,
No. 5, pp. 40–43, 2004.
112. P. Kuusk, “Luhta-mineku lugemise luhtaminek,” In: Püsimatu metaphysicus. Madis Kõiv 75, EYS Veljesto Kirjastus, Tartu, pp. 54–76,
2004.
113. P. Kuusk, “Termiitide elu,” In: Püsimatu metaphysicus. Madis Kõiv
75, EYS Veljesto Kirjastus, Tartu, pp. 16–17, 2004.
Publications • 139
114. T. Kärner, “Eesti rahvastiku hetkeseis ja tulevikuväljavaated,” Sirp,
No. 24, pp. 3–4, 2004.
115. H. Käämbre (koostaja), “Tartu Ülikooli Füüsika Instituut,” In: Eesti
teaduste tippkeskused, Eesti Teaduse tippkeskuste Ühendus, Tallinn,
Eesti, pp. 75–88, 2004.
116. H. Käämbre, “Renessansiaja inimene meie keskel (Madis Kõivu 75.
sünnipäevaks),” Maaleht, 2 dets., pp. 20, 2004.
117. H. Käämbre, “Emakeel argi- ja teaduskeelena,” Õpetajate Leht, 30.
apr., pp. 6, 2004.
118. T. Kööp, M. Lust, R. Rajamäe, E. Realo, E. Tanner jt , “Eelnõu. Väljaarvamistasemete tuletamise alused ja radionukliidide väljaarvamistasemed. Vabariigi Valitsuse 30. aprilli 2003. a. määrus nr 163,” In:
RTL, 04.05.2004, Tallinn, Eesti, 39, No. 265, 2004.
119. Ch. Lushchik, “Elutööst,” In: Eesti Vabariigi Teaduspreemiad, Eesti
Teaduste Akadeemia, pp. 10–19, 2004.
120. E. Realo, T. Kööp, M. Lust, R. Rajamäe, E. Tanner jt, “Eelnõu. Kvalifitseeritud kiirguseksperdi litsentsi ja selle taotluse vorm ning litsentsi
andmise, pikendamise, peatamise ja kehtetuks tunnistamise kord.
Keskkonnaministri 12. oktoobri 2004. a määrus nr 127,” In: RTL,
19.10.2004, Tallinn, Eesti, 134, No. 2077, 2004.
121. K. Rebane, “Kuidas saada stressi ja riskita üle Ringtee,” Tartu
Postimees, pp. 23.01., 2004.
122. K. Rebane, “Õige on atra seada,” Postimees, pp. 08.03., 2004.
123. K. Rebane, “Ajalugu muuta pole aus,” Postimees, pp. 17.09., 2004.
124. K. Rebane, “Aga tagastatud varal lasunud võlakoorem?” Äripäev,
pp. 28.09., 2004.
125. K. Rebane, “Olgem valvsad: radioaktiivne terrorism,” Äripäev,
pp. 03.12., 2004.
126. E. Tanner, T. Kööp, M. Lust, S. Nazarenko, R. Rajamäe, H. Putnik,
E. Realo jt , “Eelnõu. Kiirgusseadus. Vastu võetud 24. märtsil 2004.,”
RTL, 16.04.2004, Tallinn, Eesti, 26, No. 173, 2004.
BOOKS 2004
127. A. Aret, P. Kuusk (toimetajad), “Eesti Füüsika Seltsi aastaraamat
2003,” Tartu, pp. 112, 2004.
140 • Biannual Report 2004/2005
128. R. Koch (kaastõlkija), “Õpilase teadusentsüklopeedia (tõlge inglise
keelest The Concise Science Encyclopedia) ,” Varrak, Tallinn, pp. 320,
2004 .
129. H. Käämbre (translator), “Astronomy & Space, Communications,
Physics, Transport,” Philip`s Science & Technology, Eesti Entsüklopeediakirjastuse AS, Tallinn, Eesti, pp. 1–318, 2004.
PAPERS 2005
130. R. Aceves, T. M. Piters, S. Zazubovich, “Luminescence of excitons and
Eu2+ vc centres in KI:Eu2+,” Phys. stat. sol. (b), 242, pp. 2121–2128,
2005.
131. P. Adamson, “Scanning angle differential reflectometry around the
Brewster angle to probe ultrathin dielectric films,” Thin Solid Films,
492, pp. 221–225, 2005.
132. P. Adamson, “Reflection of light in the vicinity of of the Brewster
angel from a multilayer system of ultrathin inhomogeneous dielectric
films ,” J. Modern Opt., 52, pp. 1457–1469, 2005.
133. ȼ. Ɇ. Ⱥɝɪɚɧɨɜɢɱ, Ɇ. Ⱥ. Ȼɨɥɶɲɨɜ, ɘ. Ƚ. ȼɚɣɧɟɪ, ȿ. Ⱥ. ȼɢɧɨɝɪɚɞɨɜ,
Ƚ. ɇ. ɀɢɠɢɧ, ȼ. Ƚ. Ʉɨɥɨɲɧɢɤɨɜ, Ɉ. ɇ. Ʉɨɦɩɚɧɟɰ, Ɉ. ɇ. Ʉɨɪɨɬɚɟɜ,
ɘ. ȿ. Ʌɨɡɨɜɢɤ, ȼ. ɋ. Ʌɟɬɨɯɨɜ, Ȼ. ɇ. Ɇɚɜɪɢɧ, Ɇ. ɇ. ɉɨɩɨɜɚ, Ʉ. Ʉ. Ɋɟɛɚɧɟ, Ⱥ. ɂ. Ɋɵɫɤɢɧ, ȿ. Ⱥ. Ɋɹɛɨɜ, Ȼ. Ɇ. ɏɚɪɥɚɦɨɜ, “ɉɚɦɹɬɢ Ɋɨɦɚɧɚ
ɂɜɚɧɨɜɢɱɚ ɉɟɪɫɨɧɨ (04.01.1932 – 17.01.2002),” Ɉɩɬ. ɫɩɟɤɬɪɨɫɤ.,
98, No. 5, pp. 710–715, 2005.
134. A. Agui, T. Käämbre, C. Såthe, J. Nordgren, M. Usuda, T. Saitoh,
Y. Morimoto, “Resonant O K emission spectroscopy of layered
manganate La1.2Sr1.8Mn2O7,” J. Electron Spectrosc. Relat. Phenom.,
144–147, pp. 589–592, 2005.
135. M. Aunapuu, K. Kurrikoff, H. Tamm, A. Adojaan, T. Järveots,
T. Suuroja, S. Kõks, E. Vasar, K. Saal, A. Arend, “Morphological
investigation of transgenic with CCK2 receptor over-expression mice
brain. A pilot study,” Eesti Arst, Lisa 6, pp. 30–33, 2005.
136. V. Babin, K. Blazek, A. Krasnikov, K. Nejezchleb, M. Nikl, T. Savikhina, S. Zazubovich, “Luminescence of undoped LuAG and YAG
crystals,” Phys. stat. sol. (c), 2, No. 1, pp. 97–100, 2005.
Publications • 141
137. G. Benedek, V. Hizhnyakov, “The role of defect-induced phonon
localization in quantum diffusion,” Phys. stat. sol. (c), 2, pp. 495–498,
2005.
138. K. Blazek, A. Krasnikov, K. Nejezchleb, M. Nikl, T. Savikhina,
S. Zazubovich, “Luminescence and defects creation in Ce3+-doped
YAlO3 and LuYAlO3 crystals,” Phys. stat. sol. (b), 242, pp. 1315–
1323, 2005.
139. P. Bohacek, P. Fabeni, A. Krasnikov, M. Nikl, G. P. Pazzi, C. Susini,
S. Zazubovich, “Defects in UV-irradiated PbWO4:Mo crystals monitored by TSL measurements,” Phys. stat. sol. (c), 2, No. 1, pp. 547–
550, 2005.
140. Y. Chen, B. Liu, C. Shi, M. Kirm, M. True, S. Vielhauer, G. Zimmerer, “Luminescent properties of Gd2SiO3 powder crystal doped with
Eu3– under VUV-UV excitation,” J. Phys.: Condens. Matter, 17,
pp. 1217–1224, 2005.
141. S. Dolgov, E. Feldbach, A. Kärkkänen, T. Kärner, P. Liblik, A. Maaroos, S. Nakonechnyi, “Low-temperature (4–295 K) thermoluminescence of pure and doped MgO and CaO single crystals,” Phys. stat.
sol. (c), 2, No. 1, pp. 422–425, 2005.
142. S. Dueñas, H. Castán, H. Carc a, J. Barbolla, K. Kukli, J. Aarik,
M. Ritala, M. Leskelä, “Electrical characterization of hafnium oxide
and hafnium-rich silicate films grown by atomic layer deposition ,”
Microelectronics Reliability, 45, pp. 949–952, 2005.
143. S. Dueñas, H. Castán, H. Carcía, E. San Andrés, M. Toledano-Loque,
I. Márttil, G. González-Díaz, K. Kukli, T. Uustare, J. Aarik, “A
comparative study of the electrical properties of TiO2 films grown by
high-pressure reactive sputtering and atomic layer deposition,”
Semicond. Sci. Technol., 20, No. 10, pp. 1044–1051, 2005.
144. R. Hellborg, M. Kiisk, P. Persson, G. K. Stenström, “Vacuum in an
accelerator system – calculations and measurements,” Vacuum,
Elsevier, London, 78, No. 2, pp. 427–434, 2005.
145. V. Hizhnyakov, G. Benedek, “Quantum diffusion: effect of defectlocalized phonon dynamics,” Eur. J. Phys B, 43, pp. 431–438, 2005.
146. V. Hizhnyakov, H. Kaasik, “Emission of dielectric with oscillating
refractive index,” J. Phys. C, 21 , pp. 155–160, 2005.
142 • Biannual Report 2004/2005
147. V. Hizhnyakov, V. Boltrushko, H. Kaasik, A. Shelkan, “Multiphonon
processes in impurity centres: nonperturbative theory,” Phys. stat. sol.
(a), 202, pp. 228–234, 2005.
148. V. Hizhnyakov, V. Boltrushko, I. Tehver, “Optical transitions in the
centres with soft dynamics in the final state,” J. Phys.: Conf. Ser., 21,
pp. 161–166, 2005.
149. V. Issahanyan, T. Kärner, A. Maaroos, S. Nakonechnyi, “Spin relaxation processes in the defect hole centres of Be doped MgO single
crystals,” Phys. stat. sol. (c), 2, No. 1, pp. 426–429, 2005.
150. V. Y. Ivanov, V. A. Pustovarov, M. Kirm, E. S. Shlygin, K. I. Shirinskii, “Energy transfer in Gd2SiO5–Ce, Y2SiO5–Ce, Be2La2O5–Ce under
selective VUV- and core excitation,” Phys. Solid State, 47, pp. 1435–
1439, 2005.
151. K. V. Ivanovskikh, V. A. Pustovarov, B. V. Shulgin, M. Kirm, “Lowtemperature time-resolved luminescence VUV-spectroscopy of SrF2:Er
crystals,” Phys. Solid State, 47, pp. 1395–1397, 2005.
152. V. Jacobsen, T. Tätte, R. Branscheid, U. Maeorg, K. Saal, I. Kink,
A. Lõhmus, M. Kreiter, “Electrically conductive and optically transparent Sb-doped SnO2 STM-probe for local excitation of electroluminescence,” Ultramicroscopy, 104, No. 1, pp. 39–45, 2005.
153. T. Jantson, T. Avarmaa, H. Mändar, T. Uustare, R. Jaaniso, “Nanocrystalline Cr2O3-TiO2 thin films by pulsed laser deposition ,” Sens.
Actuators B, 109, pp. 24–31, 2005.
154. K. Jõgar, L. Metspalu, K. Hiiesaar, A. Luik, A.-J. Martin, M. Mänd,
R. Jaaniso, A. Kuusik, “Physiology of diapause in pupae of Pieris
brassicae L. (Lepidoptera: Pieridae),” Agronomy Research, 3, pp. 21–37,
2005.
155. V. Kiisk, I. Sildos, S. Lange, V. Reedo, T. Tätte, M. Kirm, J. Aarik,
“Photoluminescence characterization of pure and Sm3+–doped thin
metaloxide films,” Appl. Surf. Sci., 247, No. 1–4, pp. 412–417, 2005.
156. A. Kikas, T. Käämbre, V. Kisand, A. Saar, K. Kooser, E. Nõmmiste,
I. Martinson, “Resonant inelastic X-ray scattering at the K edge of
oxygen and fluorine in insulators,” J. Electron Spectrosc. Relat.
Phenom., 144–147, pp. 845–848, 2005.
157. A. Kikas, V. Kisand, T. Käämbre, R. Ruus, E. Nõmmiste, M. Hirsimäki, M. Valden, E. Kukk, H. Aksela, S. Aksela, “Insulating properties
Publications • 143
158.
159.
160.
161.
162.
163.
164.
165.
166.
167.
of ultrathin KF layers on Cu(100): Resonant Auger spectroscopy,”
Surface Science, 584, pp. 49–54, 2005.
J. Kikas, A. Suisalu, An. Kuznetsov, A. Laisaar, J. Takahashi,
V. Hiznyakov, “Pressure effects on relaxation in a polymer glass: A
persistent spectral hole burning study,” Opt. Spectr., 98, No. 5,
pp. 738–744, 2005.
M. Kirm, J. Aarik, M. Jürgens, I. Sildos, “Thin films of HfO2 and
ZrO2 as potential scintillators,” Nucl. Instr. Meth. Phys. Res. A, 537,
No. 5, pp. 251–255, 2005.
M. Kirm, A. Andrejczuk, J. Krzywinski, R. Sobierajski, “Influence of
excitation density on luminescence decay in Y3Al5O12:Ce and BaF2
crystals excited by free electron laser radiation in VUV,” Phys. stat. sol.
(c), 2, pp. 649–652, 2005.
M. Kirm, Y. Chen, S. Neicheva, K. Shimamura, N. Shiran, M. True,
S. Vielhauer, “VUV spectroscopy of Eu doped LiCaAlF6 and LiSrAlF6
crystals,” Phys. stat. sol (c), 2, pp. 418–421, 2005.
M. Kirm, A. Lushchik, Ch. Lushchik, “Creation of groups of spatially
correlated excitations in wide-gap solids,” Phys. stat. sol. (a), 202,
No. 2, pp. 213–220, 2005.
M. Kirm, V. N. Makhov, M. True, S. Vielhauer, G. Zimmerer,
“VUV-luminescence and excitation spectra of the heavy trivalent rare
earth ions in fluoride matrices,” Phys. Solid State, 47, pp. 1368–1375,
2005.
V. Kisand, E. Nõmmiste, E. Kukk, A. Caló, H. Aksela, S. Aksela,
“Photoexcitation, photoionisation and photofragmentation of molecular rubidium halides,” J. Electron Spectrosc. Relat. Phenom., 144–
147, pp. 175–178, 2005.
L. Kjeldgaard, T. Käämbre, J. Schiessling, I. Marenne, J. N. O'Shea,
J. Schnadt, C. J. Glover, M. Nagasono, D. Nordlund, M. G. Garnier,
L. Qian, J.-E. Rubensson, P. Rudolf, N. Mårtensson, J. Nordgren,
P. A. Brühwiler, “Intramolecular vibronic dynamics in molecular
solids: C60,” Phys. Rev. B, 72, No. 20, pp. 205414-1-4, 2005.
L. Kommel, I. Hussainova, O. Volobueva, R. Lõhmus, “Microstructural evolution and mechanical properties of nanostructured copper,”
Proc. Est. Acad. Sci. Engineering, 11 , No. 3, pp. 187–197, 2005.
P. Konsin, B. Sorkin, “Off-center displacements of Ti ions in oxide
ferroelectrics and a gigantic photo-induced dielectric constant of
144 • Biannual Report 2004/2005
168.
169.
170.
171.
172.
173.
174.
175.
176.
177.
178.
quantum paraelectric perovskite oxides in the electron-lattice theory,”
J. Physics: Conf. Series, 21, pp. 167–172, 2005.
P. Konsin, B. Sorkin, “A gigantic photoinduced dielectric constant of
quantum paraelectric perovskite oxides under a weak electric field in
the electron-lattice theory,” Ferroelectrics, 320, pp. 69–74, 2005.
P. Konsin, B. Sorkin, “Generalized multiple gap model for the superconductivity in MgB2,” J. Supercond., DOI:10.1007/s10948-0050062-6, 2005.
M. M. Korshunov, S. G. Ovchinnikov, A. V. Sherman, “Spinfluctuations and spin-exciton mechanisms of superconductivity in
cuprates,” The Physics of Metals and Metallography, 100, No. Suppl.
1, pp. S75–S78, 2005.
M. M. Korshunov, S. G. Ovchinnikov, A. V. Sherman, “Effective
Hamiltonian and the properties of normal and superconducting phases
of n-type cuprates,” Physica B, 359–361, pp. 521–523, 2005.
A. Kotlov, S. Dolgov, E. Feldbach, L. Jönsson, M. Kirm, A. Lushchik,
V. Nagirnyi, G. Svensson, B. I. Zadneprovski, “Exciton and recombination luminescence of Al2(WO4)3 crystals,” Phys. stat. sol. (c), 2,
No. 1, pp. 61–64, 2005.
V. Krasnenko, A. H. Tkaczyk, E. R. Tkaczyk, Ö. Farkas, K. Mauring,
“Vibrations-determined properties of green fluorescent protein,” Biopolymers, 78, No. 3, pp. 140–146, 2005.
A. Krasnikov, T. Savikhina, S. Zazubovich, M. Nikl, J. A. Mares,
K. Blazek, K. Nejezchleb, “Luminescence and defects creation in
Ce3+-doped aluminium and lutetium perovskites and garnets,” Nucl.
Instr. Meth. Phys. Res. A, 537, pp. 130–133, 2005.
A. Krasnikov, M. Nikl, A. Stolovits, Y. Usuki, S. Zazubovich, “Luminescence of the PbWO4:5 % Cd crystal,” Phys. stat. sol. (c), 2, pp. 77–
80, 2005.
N. Kristoffel, P. Rubin, “Effect of photodoping on cuprate superconductivity,” Physica C, 418, pp. 49–52, 2005.
N. Kristoffel, P. Rubin, “Two-component scenario, cuprate related
gaps, and superconducting density,” Proc. Estonian Acad. Sci. Phys.
Mat., 54, No. 2, pp. 98–110, 2005.
N. Kristoffel, P. Rubin, “Cuprate interband superconducting density
for doping driven spectral overlaps,” J. Superconductivity,
DOI: 10.1007/s10948-005-0063-5, 2005.
Publications • 145
179. D. Kropman, T. Kärner, U. Abru, Ü. Ugaste, E. Mellikov, “Interaction between point defects, extended defects and impurities in the
Si-SiO2 system during the process of its formation,” Mater. Sci. Engineering B, 114–115, pp. 295–298, 2004.
180. K. Kukli, J. Aarik, T. Uustare, J. Lu, M. Ritala, A. Aidla, L. Pung,
A. Hårsta, M. Leskelä, A. Kikas, V. Sammelselg, “Engineering structure and properties of hafnium oxide films by atomic layer deposition
temperature,” Thin solid Films, 479, pp. 1–11, 2005.
181. K. Kukli, M. Ritala, T. Pilvi, T. Aaltonen, J. Aarik, M. Lautala,
M. Leskelä, “Atomic layer deposition rate, phase composition and
performance of HfO2 films on noble metal and alkoxylated silicon
substrates,” Mater. Sci. Engeneering B , 118, pp. 112–116, 2005.
182. K. Kukli, T. Aaltonen, J. Aarik, J. Lu, M. Ritala, S. Ferrari, A. Hårsta,
M. Leskelä, “Atomic layer deposition and characterization of HfO2
films on noble metal film substrates ,” J. Electrochem. Soc., 152,
pp. F75–F82, 2005.
183. S. Lange, I. Sildos, V. Kiisk, M. Kirm, “Photoluminescence of
RE-doped thin metal-oxide films,” Phys. stat. sol. (c), 2, No. 1,
pp. 326–329, 2005.
184. J. Lu, J. Aarik, J. Sundqvist, K. Kukli, A. Hårsta, J.-O. Carlsson,
“Analytical TEM characterization of the interfacial layer between ALD
HfO2 film and silicon substrate,” J. Cryst. Growth, 273, pp. 510–514,
2005.
185. A. Lushchik, M. Kirm, I. Kudryavtseva, Ch. Lushchik, I. Martinson,
V. Nagirnyi, E. Vasil’chenko, “Multiplication of electronic excitations
and prospects for the increasing of scintillation efficiency in wide-gap
crystals,” Nucl. Instr. Meth. Phys. Res. A, 537, No. 1–2, pp. 45–49,
2005.
186. K. Mauring, J. Deich, F.I. Rosell, T.B. McAnaney, W.E. Moerner,
S.G. Boxer, “Enhancement of the fluorescence of the blue fluorescent
proteins by high pressure or low temperature,” J. Phys. Chem. B, 109,
No. 26, pp. 12976–12981, 2005.
187. N. Mironova-Ulmane, V. Skvortsova, A. Kuzmin, U. Ulmanis, I. Sildos, E. Cazzanelli, G. Mariotto, “Magnetic ions exchange interactions
in NiO-MgO solid solutions,” Phys. Solid State, 47, pp. 1516–1522,
2005.
146 • Biannual Report 2004/2005
188. V. Nagirnyi, A. Kotlov, L. Jönsson, M. Kirm, A. Lushchik, “Emission
decay kinetics in a CaWO4:Bi crystal,” Nucl. Instr. Meth. Phys. Res. A,
537, No. 1–2, pp. 61–65, 2005.
189. M. Nikl, H. Ogino, A. Krasnikov, A. Beitlerova, A. Yoshikawa, T. Fukuda, “Photo- and radioluminescence of Pr-doped Lu3Al5O12 single
crystal,” Phys. stat. sol. (a), 202, pp. R4–R6, 2005.
190. I. N. Ogorodnikov, V. A. Pustovarov, M. Kirm, V. S. Cheremnykh,
“A time-resolved luminescence spectroscopy study of self-trapped
excitons in NH4H2PO4 crystals,” J. Lumin., 115, pp. 69–76, 2005.
191. V. Pankratov, M. Kirm, H. von Seggern, “Intrinsic luminescence in
yttrium trifluoride,” J. Lumin., 113, pp. 143–150, 2005.
192. V. Pankratov, H. von Seggern, M. Kirm, “Excitonic luminescence and
defect formation in yttrium fluoride,” Phys. stat. sol. (c), 2, pp. 371–
374, 2005.
193. V. Peet, S. Shchemeljov, “Sum-frequency generation and multiphoton
ionization in spatially incoherent conical laser beams,” Opt. Commun.,
246, pp. 451–463, 2005.
194. H. Pettai, V. Oja, A. Freiberg, A. Laisk, “Photosynthetic activity of
far-red light in green plants,” Biochem. Biophys. Acta, 1708, pp. 311–
321, 2005.
195. H. Pettai, V. Oja, A. Freiberg, A. Laisk, “The long-wavelength limit of
plant photosynthesis,” FEBS Lett., 579, pp. 4017–4019, 2005.
196. E. Radzhabov, M. Kirm, “Triplet luminescence of cadmium centres in
alkaline-earth fluoride crystals,” J. Phys.: Condens. Matter, 17,
pp. 5821–5830, 2005.
197. E. Realo, K. Realo, “Natural radionuclides in radium-rich soils in
North-East Estonia,” J.P.McLaughlin, S.E. Simopoulos, F.Steinhäusler
(Eds.). The Natural Radiation Environment VII. Seventh Intern.
Symposium on the Natural Radiation Environment (NRE-VII), 20–24
May 2002, Rhodes, Greece. Book Series “Radioactivity in the
Environment”, vol. 7. ISBN: 0-08-044137-8, Elsevier, Amsterdam,
pp. 140–149, 2005.
198. A. Rebane, M. Drobizhev, M. Kruk, A. Karotki, I. Tehver, M. Scully ,
“Femtosecond resonance enhanced CARS for background-free
detection of organic molecules,” J. Modern Optics, 52, pp. 1243–
1253, 2005.
Publications • 147
199. Ʉ. Ʉ. Ɋɟɛɚɧɟ, “ɍɩɪɚɜɥɹɟɦɨɟ ɭɲɢɪɟɧɢɟ ɛɟɫɮɨɧɨɧɧɵɯ ɥɢɧɢɣ ɫ
ɩɨɦɨɳɶɸ ɷɮɮɟɤɬɚ Ⱦɨɩɩɥɟɪɚ ɢ ɩɟɪɫɩɟɤɬɢɜɵ ɢɫɩɨɥɶɡɨɜɚɧɢɹ ɜ
ɨɩɬɢɱɟɫɤɨɣ ɢɧɮɨɪɦɚɬɢɤɟ ɜɵɠɢɝɚɧɢɹ ɫɩɟɤɬɪɚɥɶɧɵɯ ɩɪɨɜɚɥɨɜ,”
Ɉɩɬ. ɫɩɟɤɬɪɨɫɤ., 98, No. 5, pp. 845–849, 2005.
200. K. K. Rebane, “Purely electronic zero-phonon lines in optical data
storage and processing,” Physical Chemistry, Chemical Physics
(PCCP), 7, No. 5, pp. 723–727, 2005.
201. I. Renge, “Lennard-Jones approach to optical zero-phonon spectra in
impurities in glasses,” Chem. Phys. Lett., 405, No. 4–6, pp. 404–409,
2005.
202. P. Rubin, A. Sherman, “Magnetic properties of the two-dimensional
Heisenberg model on a triangular lattice,” Phys. Lett. A, 334, No. 4,
pp. 312–316, 2005.
203. R. Ruus, K. Kooser, E. Nõmmiste, A. Saar, I. Martinson, A. Kikas,
“Cs 3d absorption and resonant photoemission study of caesium
halogenides,” Physica Scripta, T115, pp. 396–398, 2005.
204. R. Ruus, E. Kukk, M. Huttula, H. Aksela, S. Aksela, “Resonant VUV
absorption in CsCl monomers and dimers – experiment and theory,”
J. Electron Spectrosc. Relat. Phenom., 144–147, pp. 1215–1218,
2005.
205. M. Rätsep, C. N. Hunter, J. D. Olsen, A. Freiberg, “Band structure
and local dynamics of excitons in bacterial light-harvesting complexes
revealed by spectrally selective spectroscopy,” Photosynth. Res., 86,
pp. 37–48, 2005.
206. P. Saari, M. Menert, H. Valtna, “Photon localization barrier can be
overcome,” Opt. Commun., 246, No. 4–6, pp. 445–450, 2005.
207. F. A. Savikhin, A. Kasikov, “A new look at the formation of old
believer communities in the Western Prichud’e of Estonia (on the Basis
of Historical and Linguistic Data),” Russian Linguistics, Springer, 29,
No. 2, pp. 137–187, 2005.
208. F. Savikhin, M. Kerikmäe, E. Feldbach, A. Lushchik, D. Onishchik,
D. Rakhimov, I.Tokbergenov, “Fast intrinsic emission with the
participation of oxyanion and cation excitations in metal sulphates,”
Phys. stat. sol. (c), 2, No. 1, pp. 252–255, 2005.
209. J. Schiessling, L. Kjeldgaard, T. Käämbre, I. Marenne, J. N. O'Shea,
J. Schnadt, C. J. Glover, M. Nagasono, D. Nordlund, M. G. Garnier,
L. Qian, J.-E. Rubensson, P. Rudolf, N. Mårtensson, J. Nordgren,
148 • Biannual Report 2004/2005
210.
211.
212.
213.
214.
215.
216.
217.
218.
219.
P. A. Brühwiler, “Bulk and surface charge states of K3C60,” Phys. Rev.
B, 71, No. 16, pp. 165420-1-16, 2005.
D. Schiffbauer, C. Wickleder, G. Meyer, M. Kirm, M. Stephan,
P. C. Schmidt, “Crystal structure, electronic structure and luminescence of Cs2KYF6:Pr3+,” Z. Anorg. Allg. Chem., 631, pp. 3046–
3052, 2005.
A. Sherman, M. Schreiber, “Resonance peak and incommensurability
in cuprate perovskites,” The Physics of Metals and Metallography,
100, No. Suppl. 1, pp. S86–S89, 2005.
A. Sherman, “Magnetic properties of cuprate perovskites,” In: Proc.
NATO ARW “Smart Materials for Ranging Systems”, Krasnoyarsk,
Russia, 29 August – 1 September 2004, Kluwer 2005, pp. 115–128,
2005.
A. Sherman, “Incommensurate magnetic response in cuprate
perovskites,” Phys. Lett. A, 337, No. 4–6, pp. 435–440, 2005.
A. Sherman, M. Schreiber, “Incommensurate spin dynamics in underdoped cuprate perovskites,” Intern. J. Modern Phys. B, 19, No. 13,
pp. 2145–2159, 2005.
A. Stolovits, A. Sherman, R. K. Kremer, Hj. Mattausch, H. Okudera,
X-M. Ren, A. Simon, J. R. O’Brien, “Quantum interference of electrons
in Nb5– Te4 single crystals,” Phys. Rev. B, 71, pp. 144519, 2005.
T. Tamm, J. Linnanto, A. Ellervee, A. Freiberg, “Modeling of pressure
effects on absorption spectra of solvated chlorophyll and bacteriochlorophyll molecules,” In: Lecture Series on Computer and
Computational Sciences, Brill Academic Publishers, 3A, pp. 550–553,
2005.
I. Tehver, “Transform relations for CARS excitation profiles,” Phys.
stat. sol. (c): Conf. and Critical Reviews, 2, pp. 499–502, 2005.
K. Timpmann, G. Trinkunas, P. Qian, C. N. Hunter, A. Freiberg,
“Excitons in core LH1 antenna complexes of photosynthetic bacteria:
Evidence for strong exciton coupling and off-diagonal disorder,”
Chem. Phys. Lett., 414, pp. 359–363, 2005.
S. N. Tkachev, M. H. Manghnani, A. Niilisk, J. Aarik, H. Mändar,
“Raman and Brillouin scattering spectroscopy studies of atomic-layerdeposited ZrO2 and HfO2 thin films,” Spectrochimica Acta A, 61,
pp. 2434–2438, 2005.
Publications • 149
220. S. N. Tkachev, M. H. Manghnani, A. Niilisk, J. Aarik, H. Mändar,
“Micro-Raman spectroscopy and X-ray diffraction studies of atomiclayer-deposited ZrO2 and HfO2 thin films,” J. Mater. Sci., 40,
pp. 4293–4298, 2005.
221. G. Trinkunas, A. Freiberg, “Abrupt exciton self-trapping in finite and
disordered one-dimensional aggregates,” J. Lumin., 112, pp. 420–423,
2005.
222. E. Vasil’chenko, I. Kudryavtseva, A. Lushchik, Ch. Lushchik,
V. Nagirnyi, “Selective creation of colour centres and peaks of
thermally stimulated luminescence by VUV photons in LiF single
crystals,” Phys. stat. sol. (c), 2, No. 1, pp. 405–408, 2005.
223. A. Voloshinovskii, S. Zazubovich, G. Stryganyuk, I. Pashuk, “Luminescence of CsBr:Tl crystals under synchrotron excitation,” J. Lumin.,
111, pp. 9–15, 2005.
224. K. Õige, T. Avarmaa, A. Suisalu, R. Jaaniso, “Effect of long-term
aging on oxygen sensitivity of luminescent Pd-tetraphenylporphyrin/
PMMA films,” Sens. Acuators B, 106, pp. 424–430, 2005.
PROCEEDINGS 2005
225. J. Aarik, A. Kasikov, M. Kirm, S. Lange, T. Uustare, H. Mändar,
“Optical properties of crystalline Al2O3 thin films grown by atomic
layer deposition,” In: Proc. SPIE – Optical Materials and Applications,
5946, pp. 1–10 , 2005.
226. P. Adamson, “Characteristic reflection angles of nanoscopic layered
media and optical probing dielectric films,” In: Proc. SPIE – Optical
Materials and Applications, 5946, pp. 336–345, 2005.
227. P. Adamson, “Reflection characteristics of nanoscopic anisotropic
layered structures and optical diagnostics of nanofilms,” In: 5th IEEE
Intern. Conf. on Nanotechnology (IEEE Cat No. 05TH8816) , IEEE,
1, pp. 255–258, 2005.
228. P. Adamson, “Long-wavelength approximation theory of light
reflection from nanoscale media,” In: Technical Proc. 2005 NSTI
Nanotechnology Conf. and Trade Show, NSTI, 3, pp. 664–667,
2005.
150 • Biannual Report 2004/2005
229. P. Adamson, “Differential reflection characteristics for optical probing
of nanoscale anisotropic layered system,” In: Intern. Conf. on MEMS,
NANO and Smart Systems, IEEE Comput. Soc., pp. 307–313, 2005.
230. V. Babin, K. Blazek, A. Krasnikov, K. Nejezchleb, M. Nikl, T. Savikhina, S. Zazubovich, “Intrinsic luminescence of LuAG and YAG
crystals,” In: HASYLAB Activity Report 2004, DESY, Hamburg,
Germany, pp. 271–272, 2005.
231. V. Babin, M. Kink, Y. Maksimov, K. Nejezchleb, M. Nikl, S. Zazubovich, “Antisite defects study in undoped and Ce3+-doped LuScAG
and LuYAG crystals: influence of scintillating efficiency,” In:
HASYLAB Activity Report 2005, DESY, Hamburg, Germany, Part I,
pp. 261–262, 2005.
232. A. Calo, E. Kukk, S. Osmekhin, E. Nõmmiste, V. Kisand, M. Huttula, H. Aksela, S. Aksela, “The electronic decay of VUV excited
resonant states of rubidium halides,” In: MAX-LAB Activity Report
2004, National Laboratory, Lund, Sweden, pp. 110–111, 2005.
233. G. Corradi, A. Kotlov, A. Lushchik, V. Nagirnyi, “3d10o3d94s and
3d10o3d94p electronic transitions in Li2B4O7:Cu single crystals,” In:
HASYLAB Activity Report 2005, DESY, Hamburg, Germany, Part I,
pp. 717–718, 2005.
234. S. Dolgov, E. Feldbach, A. Kotlov, I. Kudryavtseva, A. Lushchik,
A. Maaroos, I. Martinson, V. Nagirnyi, E. Vasil’chenko, “Lowtemperature electron-hole processes in Li4SiO4 ceramics,” In: MAXLab Activity Report 2004, National Laboratory, Lund, Sweden,
pp. 114–115, 2005.
235. E. Feldbach, A. Kotlov, L. Jönsson, M. Kirm, A. Lushchik,
V. Nagirnyi, “Recombination luminescence of CaSO4 powders,” In:
MAX-Lab Activity Report 2004, National Laboratory, Lund, Sweden,
pp. 116–117, 2005.
236. E. Feldbach, M. Kirm, P. Liblik, A. Maaroos, H. Mändar, “Electronic
excitations and luminescence in naturally nanoporous C12A7
compound,” In: HASYLAB Activity Report 2005, DESY, Hamburg,
Germany, Part I, pp. 325–326, 2005.
237. V. Hizhnyakov, V. Boltrushko, “Anomalous optical spectra of centers
with soft phonon dynamics in excited state,” In: Proc. SPIE - Optical
Materials and Applications, 5946, pp. 192–201, 2005.
Publications • 151
238. V. Ivanov, M. Kirm, V. Pustovarov, A. Kruzhalov, “Inner-shell excitation of intrinsic luminescence in oriented BeO crystals,” In:
HASYLAB Activity Report 2005, DESY, Hamburg, Germany, Part I,
pp. 669–670, 2005.
239. R. Jaaniso, T. Avarmaa, A. Suisalu, A. Floren, A. Ruudi, K. Õige,
“Stability of luminescence decay parameters in oxygen sensitive
polymer films doped with Pd-porphyrins,” In: Proc. SPIE – Optical
Materials and Applications, 5946, pp. 150–159, 2005.
240. E. Jalviste, N. Ohta, “Electric field induced reorientation of polar
molecules in a poly(methyl methacrylate) film studied by electroabsorption spectroscopy,” In: Proc. SPIE – Optical Materials and
Applications, 5946, pp. 160–171, 2005.
241. I. Jõgi, J. Aarik, K. Kukli, H. Käämbre, M. Laan, J. Lu, T. Sajavaara,
T. Uustare, “The effect of precursors on the structure and conductivity
of atomic layer deposited TiO2 films,” Electrochem. Soc. Proc., 2005–
09, pp. 575–582, 2005.
242. A. Kikas, M. Valden, M. Hirsimäki, V. Kisand, K. Kooser,
T. Käämbre, E. Nõmmiste, “Ultrathin films of KCl on Cu(100):
photoelectron and resonant Auger Spectroscopy,” In: MAX-LAB
Activity Report 2004, National Laboratory, Lund, Sweden, pp. 368–
369, 2005.
243. A. Kikas, T. Käämbre, V. Kisand, K. Kooser, E. Nõmmiste, V. Ivanov, V. Pustovarov, I. Martinson, “Resonantly excited X-ray fluorescence in BeO,” In: MAX-LAB Activity Report 2004, National
Laboratory, Lund, Sweden, pp. 224–225, 2005.
244. M. Kirm, V. V. Harutunyan, V. N. Makhov, S. Vielhauer, “VUV
luminescence of as-grown and electron irradiated corundum single
crystals,” In: Proc. SPIE – Optical Materials and Applications, 5946,
pp. 41–46, 2005.
245. M. Kirm, A. Gektin, V. Nagirnyi, V. Nesterkina, K. Shimamura,
N. Shiran, E. Villora, “VUV Spectroscopy of a Ca0,65Eu0,35F3,35 single
crystal,” In: HASYLAB Activity Report 2005, DESY, Hamburg,
Germany, Part I, pp. 569–570, 2005.
246. M. Kleemann, A. Suisalu, J. Kikas, “Polymer film doped with solvatochromic dye for humidity measurement,” In: Proc. SPIE – Optical
Materials and Applications, 5946, pp. 172–178, 2005.
152 • Biannual Report 2004/2005
247. N. Kristoffel, P. Rubin, “Dependence of the superconducting effective
mass on doping in cuprates,” cond-mat/ 0506317, 2005.
248. N. Kristoffel, T. Örd, P. Rubin, “Cuprate interband model and
doping dependence of the coherence length,” cond-mat/ 0504431,
2005.
249. A. Laisaar, A. Suisalu, An. Kuznetsov, J. Kikas, “High-pressure lowtemperature spectroscopy of pyrene molecules in commensurate and
incommensurate phases of biphenyl,” In: Proc. Joint 20th AIRAPT43rd EHPRG Intern. Conf. on High Pressure Science and Technology, Eds. E.Dinjus, N.Dahmen, No. T5-P129, pp. 1–10, 2005.
250. R. Lõhmus, I. Hussainova, L. Kommel, H. Siimon, “AFM analysis of
nano-copper surface morphology,” In: Mechanical Properties of
Nanostructured Materials – Experiments and Modeling, Eds.
J. G. Swadener, E. Lilleodden, S. Asif, D. Bahr, and D. Weygand
(Mater. Res. Soc. Symp. Proc. 880E, Warrendale, PA, 2005),
pp. BB5.3.1, 2005.
251. A. Lushchik, A. Kotlov, Ch. Lushchik, V. Nagirnyi, K. Schwartz,
E. Vasil’chenko, “Anion excitations in virgin and swift ion irradiated
LiF single crystals,” In: HASYLAB Activity Report 2005, DESY,
Hamburg, Germany, Part I, pp. 257–258, 2005.
252. A. Lushchik, Ch. Lushchik, E. Feldbach, I. Kudryavtseva, P. Liblik,
A. Maaroos, V. Nagirnyi, F. Savikhin, E. Vasil’chenko, “Photon
multiplication in wide-gap BAM and SAM aluminates,” In: Proc. SPIE
– Optical Materials and Applications, 5946, pp. 61–72, 2005.
253. V. N. Makhov, J. C. Krupa, M. Kirm, G. Stryganyuk, S. Vielhauer,
G. Zimmerer, “VUV luminescence of Lu3+ ions in fluoride matrices,”
In: HASYLAB Activity Report 2005, DESY, Hamburg, Germany,
Part I, pp. 709–710, 2005.
254. N. Mironova-Ulmane, V. Skvortsova, A. Kuzmin, I. Sildos, “Influence
of radiation defects on exciton-magnon interactions in nickel oxide,”
In: Proc. SPIE – Optical Materials and Applications, 5946, pp. 93–97,
2005.
255. A. Niilisk,
J. Aarik,
T. Uustare,
H. Mändar,
S. Tkachev,
M. H. Manghnani, “A structural study of ZrO2 and HfO2 thin films
grown by atomic layer deposition,” In: Proc. SPIE – Optical Materials
and Applications, 5946, pp. 98–105, 2005.
Publications • 153
256. I. Ots, H. Liivat, “Asümptootiline vabadus kvantkromodünaamikas,”
In: Eesti Füüsika Seltsi aastaraamat 2004, Eesti Füüsika Selts, XV,
pp. 46–57, 2005.
257. I. Rebane, “Spontaneous emission rates of a single-impurity molecule
in dependence on its orientation in biaxial host crystal,” In: Proc. SPIE
– Optical Materials and Applications, 5946, pp. 202–209, 2005.
258. K. Rebane, “Requirements to impurity activated solids as materials for
optical data storage and processing,” In: Proc. SPIE – Optical
Materials and Applications, 5946, pp. 210–214, 2005.
259. V. Reedo, S. Lange, V. Kiisk, T. Tätte, A. Lukner, I. Sildos,
“Influence of ambient gas on the photoluminescence of sol-gel derived
TiO2:Sm3+ films,” In: Proc. SPIE – Optical Materials and Applications,
5946, pp. 106–111, 2005.
260. I. Renge, “Lennard-Jones model of disorder in solids,” In: Proc. SPIE
– Optical Materials and Applications, 5946, pp. 215–223, 2005.
261. A. Rosental, “Introduction,” In: Proc. SPIE – Optical Materials and
Applications, 5946, pp. xiii, 2005.
262. K. Saal, M. Plaado, I. Kink, A. Kurg, V. Kiisk, J. Koževnikova,
U. Mäeorg, A. Rinken, I. Sildos, T. Tätte, A. Lõhmus, “Aminopropyl
embedded silica films as potent substrates in DNA microarray
applications,” In: Biological and Bio-Inspired Materials and Devices
(Mater. Res. Soc. Symp. Proc. 873E, Warrendale, PA, 2005), pp. K93,
2005 (CDR-10, ISBN:1-55899-821-7).
263. V. Sammelselg, J. Aarik, A. Kikas, R. Rammula, T. Käämbre,
K. Kooser, A. Zakharov, M. Lulla, I. Martinson, “Study of growth
process of ultrathin alumina films deposited on silicon substrates,” In:
MAX-LAB Activity Report 2004, National Laboratory, Lund, Sweden,
pp. 78–79, 2005.
264. M. Selg, “Reference potential approach to the quantum-mechanical
inverse problem: I. Calculation of phase shift and Jost function,”
arXiv:quant-ph/0506064, pp. 1–21, 2005.
265. M. Selg, “Reference potential approach to the quantum-mechanical
inverse problem: II. Solution of Krein equation,” arXiv:quantph/0506130, pp. 1–22, 2005.
266. M. Selg, “Reference potential approach to the inverse Schrödinger
problem: explicit demonstration of Levinson theorem and a solution
154 • Biannual Report 2004/2005
scheme for Krein equation,” arXiv:quant-ph/0512118, pp. 1–26,
2005.
267. M. Selg, “Reference potential approach to the inverse problem in
quantum mechanics,” In: The Nineteenth Colloquium on High
Resolution Molecular Spectroscopy, Editors: D. Bermejo, J. L. Domenech, M. A. Moreno, ISBN 84-609-6737-9, Universidad de Salamanca, pp. 190–191, 2005.
268. A. Tarre, A. Rosental, T. Uustare, A. Kasikov, “SnO2 on sapphire”,
In: Proc. SPIE – Optical Materials and Applications, 5946, pp. 128–
134, 2005.
269. T. Tätte, V. Jacobsen, M. Paalo, R. Branscheid, M. Kreiter, U. Maeorg, K. Saal, A. Lõhmus, I. Kink, “Preparation of Sb doped SnO2
SPM tips and their use as transparent probes in STM induced light
hybrid microscopy,” In: NSTI Nanotech 2005, NSTI Nanotechnology
Conf. and Trade Show, Anaheim, CA, United States, 3, pp. 305–308,
2005.
POPULAR SCIENTIFIC ARTICLES, PUBLICISM 2005
270. A. Freiberg, “Kõige tähtsam energeetika,” Horisont , No. 5, pp. 12–
19, 2005.
271. A. Kasikov, “Türgi – riik või ajalugu?” Eesti Päevaleht, No. 3. jaanuar,
pp. , 2005.
272. A. Kikas, “Sünkrotronkiirgus aatomit puurimas,” Horisont, Tallinn, 4,
pp. 22–26, 2005.
273. V. Kisand, “Tehnika elushoidmise asemel eksperiment,” Horisont,
Tallinn, 3, pp. 28–29, 2005.
274. R. Koch, “Okupatsioonist meis ja meie ümber,” Ajaleht “Rahvuslik
Koguja”, Tartu, Eesti, No. 2(35), p. 1, 2005.
275. P. Kuusk, I. Martinson, “Eesti Füüsikud võõrsil IV,” In: Eesti Füüsika
Seltsi aastaraamat 2004, Eesti Füüsika Selts, XV, pp. 35–45, 2005.
276. P. Kuusk, “Eessõna,” In: Eesti Füüsika Seltsi aastaraamat 2004, Eesti
Füüsika Selts, XV, pp. 3, 2005.
277. P. Kuusk, “Albert Einsteini artikkel “Liikuvate kehade elektrodünaamikas (koos selle artikli I osa tõlkega),” Akadeemia, No. 7,
pp. (1392)-1408-1425, 2005.
Publications • 155
278. P. Kuusk, “Madis Kõiv,” Estonian Culture, Estonian Institute, IV,
No. II, pp. http://www.einst.ee/culture/II_MMIV/kuusk.html, 2005.
279. T. Kärner, “Globaalsetest kriisidest,” Akadeemia, No. 9, pp. 1874–
1890, 2005.
280. T. Kärner, “Eesti välispoliitika dilemmast,” Sirp, No. 33, p. 3, 2005.
281. H. Käämbre, “Koherents ja laserkamm tõid Nobeli preemia,”
Horisont, Tallinn, 6, pp. 26–27, 2005.
282. T. Käämbre, “Nüüd oma uurimisrühm Tartus,” Horisont, Tallinn, 6,
pp. 30–31, 2005.
283. E. Nõmmiste, “Loodusteaduslik mõtteviis on hädavajalik,” Horisont,
Tallinn, 1, pp. 17, 2005.
284. E. Nõmmiste, “Eredam kui tuhat päikest,” Horisont, Tallinn, 3,
pp. 20–27, 2005.
285. E. Realo (eelnõu kaasautor), “Keskkonnaministri 26. mai 2005. a
määrus nr 45. Kiirgustöötaja ja elaniku efektiivdooside seire ja
hindamise kord ning radionukliidide sissevõtust põhjustatud dooside
doosikoefitsientide ning kiirgus- ja koefaktori väärtused,” RTL,
16.06.2005, Tallinn, Eesti, 65, No. 934, 2005.
286. E. Realo (eelnõu kaasautor), “Keskkonnaministri 15. veebruari 2005. a
määrus nr 10. Kiirgustegevuses tekkinud radioaktiivsete ainete või
radioaktiivsete ainetega saastunud esemete vabastamistasemed ning
nende vabastamise, ringlusse võtmise ja taaskasutamise tingimused,”
RTL, 01.03.2005, Tallinn, Eesti, 24, No. 331, 2005.
287. E. Realo (eelnõu kaasautor), “Keskkonnaministri 9. veebruari 2005. a
määrus nr 8. Radioaktiivsete jäätmete klassifikatsioon, registreerimise,
käitlemise ja üleandmise nõuded ning radioaktiivsete jäätmete
vastavusnäitajad,” RTL, 17.02.2005, Tallinn, Eesti, 20, No. 244,
2005.
288. K. Rebane, “Terrorism – tsivilisatsiooni tulevik?” Akadeemia, No. 6,
pp. 1175–1187, 2005.
289. K. Rebane, “Veel mõni sõna terrorismiohust,” Akadeemia, No. 12,
pp. 2742, 2005.
290. K. Rebane, “Erasektor tervishoiule appi,” Äripäev, 10.01.2005.
291. K. Rebane, “Ahistav vanusepiir,” Postimees, 11.05.2005.
292. K. Rebane, “Õiglustunne avaramaks,” Postimees, 09.11.2005.
293. A. Rosental, “Nanotehnoloogia,” In: Eesti Teadusfondi Aastaraamat
2004, Eesti Teadusfond, pp. 14, 2005.
156 • Biannual Report 2004/2005
294. Ɏ. ɋɚɜɢɯɢɧ,
Ⱥ. Ʉɚɫɢɤɨɜ, “ɍɧɢɤɚɥɶɧɨɫɬɶ ɫɬɚɪɨɨɛɪɹɞɱɟɫɬɜɚ
ɗɫɬɨɧɢɢ ɢ ɫɨɫɬɚɜɚ ɫɥɨɜ ɹɡɵɤɚ ɫɬɚɪɲɟɝɨ ɩɨɤɨɥɟɧɢɹ ɪɭɫɫɤɢɯ
Ɂɚɩɚɞɧɨɝɨ ɉɪɢɱɭɞɶɹ ɫɟɪɟɞɢɧɵ 20 ɜɟɤɚ,” In: Ⱦɟɧɶ ɤɭɥɶɬɭɪɵ
ɉɪɢɱɭɞɶɹ, Ɍɚɥɥɢɧɧ 2005, p. 8.15, 2005.
295. Ɏ. ɋɚɜɢɯɢɧ, Ⱥ. Ʉɚɫɢɤɨɜ, “Ɋɭɫɫɤɢɟ ɜ ɉɪɢɱɭɞɶɟ: Ʉɬɨ ɨɧɢ?”
Ɇɨɥɨɞɺɠɶ ɗɫɬɨɧɢɢ, 27 ɦɚɹ, 3 ɢɸɧɹ, 17 ɢɸɧɹ, 2005.
296. Ɏ. ɋɚɜɢɯɢɧ, Ⱥ. Ʉɚɫɢɤɨɜ, “Ɉ ɩɪɚɜɨɫɥɚɜɧɵɯ ɜ ɩɨɥɶɫɤɨ–ɲɜɟɞɫɤɢɣ
ɩɟɪɢɨɞ,” Peipsirannik, No. 4, 2005.
BOOKS, BOOKLETS 2005
297. M. Kiisk, E. Realo (tõlkijad), “Tuumasünteesiuuringud: võimalik tulevikuenergia Euroopa jaoks (Tõlge eesti keelde),” Euroopa Ühenduste
Ametlike Väljaannete Talitus, ISBN 92-894-7723-7, Euroopa Komisjon, Luksemburg, 40 pp., 2005 .
298. M. Kiisk, E. Realo (tõlkijad), “ITER. Termotuumaenergia maailmale
(Tõlge eesti keelde),” Seeria: Euroopa uurimistegevus huviorbiidis,
Euroopa Komisjon, Informatsiooni- ja kommunikatsiooniosakond,
Brüssel, 8 pp., 2005.
299. A. Rosental (editor), “Optical Materials and Applications,” Proc. SPIE
– Optical Materials and Applications, 5946, pp. xiii,1–530, 2005.
6. TALKS AND POSTERS
AT CONFERENCES
ORAL PRESENTATIONS 2004
1.
2.
3.
4.
5.
6.
7.
8.
J. Aarik. In situ QCM studies of atomic layer deposition of high-k oxides.
ALD2004, Helsinki, Finland, Aug. 16–18, 2004 (invited paper).
M. Agåker, J. Söderström, T. Käämbre, C. Glover, L. Gridneva,
T. Schmitt, A. Augustsson, M. Mattesini, R. Ahuja, and J. E. Rubensson. Resonant inelastic soft X-ray scattering at hollow lithium states in
solids. The 14th Intern. Conf. on Vacuum Ultraviolet Radiation
Physics, Cairns, Australia, July 19–23, 2004.
V. Fedoseyev. Reflection and refraction of a light beam carrying the
angular orbital momentum. 3rd Intern. Conf. „Basic Problems of
Optics”, St. Petersburg, Russia, October 18–21, 2004.
A. Freiberg. Õppetooli ülevaade. TÜMRI ja Eesti Biokeskuse aastakonverents 2003, Tartu, 13.–14. dets., 2004.
A. Freiberg. Pettus teaduses. Tartu Rotary lõuna, Tartu, 19. märts
2004.
A. Freiberg, M. Rätsep, K. Timpmann. Low-lying excitonic polaron
states in core LH1 and peripheral LH2 bacterial light-harvesting complexes: A hole burning and fluorescence line narrowing study. Conf. of ESF
Femtochemistry & Femtobiology (ULTRA) Program, Pecs, Hungary,
March 25–28, 2004 (invited paper).
A. Freiberg. Excitonic polarons in photosynthesis. PS 2004 LightHarvesting Systems Workshop, Sainte-Adele, Canada, Aug. 26–29,
2004 (invited paper).
V. Hizhnyakov, V. Boltrushko. Anomalous optical spectra of centers with
soft phonon dynamics in the excited state. 4th Intern. Conf. on Advanced
Optical Materials and Devices (AOMD-4), Tartu, Estonia, July 6–9,
2004 (invited paper).
158 • Biannual Report 2004/2005
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
V. Hizhnyakov, G. Benedek. Quantum diffusion: effects of local
distortion of phonons. 11th Intern. Conf. on Phonon Scattering in
Condensed Matter (Phonons 2004), St. Petersburg, Russia, July 25–
30, 2004.
V. Hizhnyakov, V. Boltrushko, H. Kaasik, A. Shelkan. Multiphonon
processes in impurity centres: nonperturbative theory. 15th Intern. Conf.
on Defects in Insulating Materials (ICDIM-2004), Riga, Latvia, July
11–16, 2004 (invited paper).
R. Jaaniso, T. Avarmaa, A. Suisalu, A. Floren, A. Ruudi, K. Õige.
Stability of luminescence decay parameters in oxygen-sensitive polymer films
doped with Pd-porphyrins. 4th Intern. Conf. on Advanced Optical
Materials and Devices (AOMD-4), Tartu, Estonia, July 6–9, 2004.
M. Kiisk. Improvement of the AMS-technique at the Lund AMS facility”.
Seminar Central 14C Analysis Facility, Max-Planck-Institute for
Biogeochemistry , Jena, Saksamaa, February 9, 2004.
M. Kiisk. Experience and improvement of the AMS-technique at the Lund
AMS facility. Seminar Ion Beam Physics, ETH Institute for Particle
Physics, Zürich, Šveits, March 15, 2004.
J. Kikas, A. Suisalu, An. Kuznetsov, A. Laisaar, V. Hizhnyakov.
Pressure Effect on Relaxation in Glasses: A Persistant Spectral Hole
Burning Study. High Resolution Site Selective Spectroscopy, An Intern.
Conf. in Memory of Roman I. Personov, Bayreuth, Germany, July 15–
18, 2004 (invited paper).
A. Kikas. Creation and Decay of X-Ray Excitations in ionic solids.
Synchrotron Radiation Summer School, Kääriku, Estonia, June 2–4,
2004.
A. Kikas. Röntgenkiirguse Ramani hajumine. XXXIV Eesti Füüsikapäevad, Tartu Estonia, 13.–14.veebr. 2004.
A. Kikas. Sünkrotronkiirgus: Mis, Kuidas, Milleks?. Noorfüüsikute
sügiskool, Kääriku, Estonia, Oct. 8–10, 2004.
M. Kirm, A. Lushchik, Ch. Lushchik. Creation of groups of spatially
correlated excitations in wide-gap solids. 15th Intern. Conf. on Defects
in Insulating Materials (ICDIM-2004), Riga, Latvia, July 11–16, 2004
(invited paper).
V. Kisand, E. Nõmmiste, E. Kukk, M. Huttula, A. Koivukangas,
A. Calo, H. Aksela, S. Aksela. Photoexcitation, –ionization and fragmentation of molecular CsCl and rubidium halides. Meeting of the NORFA
Talks and Posters at Conferences • 159
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
financed network “Synchrotron-based electron spectroscopy”, Tartu,
Estonia, March 15, 2004.
M. Kleemann, A. Suisalu, J. Kikas. Polymer film doped with solvatochromic dye for humidity measurement. 4th Intern. Conf. on Advanced
Optical Materials and Devices (AOMD-4), Tartu, Estonia, July 6–9,
2004.
R. Koch. Tartu rahu 84. aastapäeval. Tartu rahulepingu sõlmimise 84.
aastapäevale pühendatud kõnekoosolek, Tartu, Eesti, 2. veebr. 2004
(invited paper).
K. Kooser, R. Ruus, A. Saar, E. Nõmmiste, A. Kikas. Cs 3d absorption
and resonant photoemission study of caesium halogenides. Meeting of the
NORFA financed network “Synchrotron-based electron spectroscopy”,
Tartu, Estonia, March 15, 2004.
A. Krasnikov, M. Nikl, S. Zazubovich. Origin of green emission in
PbWO4 crystals. 15th Intern. Conf. on Defects in Insulating Materials
(ICDIM-2004), Riga, Lavia, July 11–16, 2004.
N. Kristoffel, P. Rubin. Cuprate energetic characteristics in a multiband
scenario with doping driven spectral overlaps. 4th Intern. Conf. Nanoscale Heterogeneity and Quantum Phenomena in Complex Matter
(Stripes and Superconductivity, Stripes04), Rome, Italy, Sept.26–
Oct.2, 2004 (invited paper).
N. Kristoffel, P. Rubin. Kupraatülijuhtide energeetilised karakteristikud
ja nende seosed dopeeringskaalal. XXXIV Eesti Füüsikapäevad, Tartu,
Estonia, 13.–14.veebr. 2004.
E. Kukk, M. Huttula, J. Rius i Riu, H. Aksela, S. Aksela, R. Ruus.
VUV-induced processes in alkali halide dimer molecules – how well does
the ionic approach work? The 14th Intern. Conf. on Vacuum Ultraviolet Radiation Physics, Cairns, Australia, July 19–23, 2004.
K. Kukli, M. Ritala, T. Pilvi, T. Aaltonen, J. Aarik, M. Leskelä. Factors
influencing atomic layer deposition rate and phase composition of high
permittivity oxide layers. E-MRS2004, Strasbourgh, France, May 24–
28, 2004.
P. Kuusk. Mida teha populaarteadusliku kirjandusega. VI semiootika
sügiskool, Kääriku, 6.–7.nov., 2004.
H. Käämbre. Eesti teaduskeelest ja argikeelest. Kuku raadio saates
Keelekuku, Tartu, Estonia, Nov. 8, 2004.
160 • Biannual Report 2004/2005
30. H. Käämbre. Mikrokeeriste maailmas (2003.a. Nobeli füüsikapreemiast).
XXXIV Eesti Füüsikapäevad, Tartu, Estonia, Febr. 13, 2004.
31. H. Käämbre. Mikrokeeriste maailmas (2003.a. Nobeli füüsikapreemiast).
Eesti füüsikaõpetajate päev, Tallinn, Estonia, March 24, 2004.
32. H. Käämbre. Mikrokeeriste maailmas (2003.a. Nobeli füüsikapreemiast).
Tallinna Reaalkoolis, Tallinn, Estonia, April 14, 2004.
33. H. Käämbre. Emakeel argi- ja teaduskeelena. F.J. Wiedemanni keelepäev, Väike-Maarja, Estonia, April 21, 2004.
34. H. Käämbre. Emakeel argi- ja teaduskeelena. Eesti Kirjanduse Seltsi
koosolek, Tallinn, Estonia, May 15, 2004.
35. H. Käämbre. Laser-mis? kuidas? milleks? Loeng TÜ biogeoteaduskonna
üliõpilastele (prof. A. Freibergi loengukursuse raames), Tartu, Estonia,
Nov. 3, 2004.
36. H. Liivat, I. Ots. Nobeli preemia füüsikas 2004. EFS noorte füüsikute
VI sügiskool, Kääriku, 8.–10.okt. 2004.
37. A. Lushchik, Ch. Lushchik, P. Liblik, A. Maaroos, V. Nagirnyi,
F. Savikhin. Photon multiplication in wide-gap BAM and SAM aluminates. 4th Intern. Conf. on Advanced Optical Materials and Devices
(AOMD-4), Tartu, Estonia, July 6–9, 2004 (invited paper).
38. M. Lust, H. Putnik, E. Realo. Preliminary Long-Term Radiological
Safety Assessment for the Paldiski Radioactive Waste Interim Storage
Facility, Estonia. Baltic-Swedish Seminar Transfer of knowledge and
experience in safety and risk assessment methods for radwaste facilities,
Studsvik, Sweden , 23–27 February, 2004 (invited paper).
39. A. Lõhmus. Force interactions in nanowire-based nanoelectromechanical
devices. 3rd ESF Nanotribology Workshop, Sesimbra, Portugal, Sept.
18–24, 2004.
40. E. Nõmmiste, V. Kisand, M. Valden, M. Hirsimäki, E. Kukk,
T. Käämbre, R. Ruus, A. Kikas. Studing KF monolayers on copper
substrate. Fifth Nordic Conf. on Surface Science, Tampere, Finland,
Sept. 22–25, 2004.
41. E. Realo. Kiirgusohutus täna ja homme. Eesti Radioloogia Ühingu
õppepäev, Põlva, Eesti, 5. juuni 2004 (invited paper).
42. I. Rebane. Spontaneous emission rates of a single impurity molecule in
dependence on its orientation in biaxial host crystal. 4th Intern. Conf. on
Advanced Optical Materials and Devices (AOMD-4), Tartu, Estonia,
July 6–9, 2004.
Talks and Posters at Conferences • 161
43. K. Rebane. Aatomituumade madala energiaga isomeerseisundid. Uus
laine? XXXIV Eesti Füüsikapäevad, Tartu, Estonia, Febr. 13–14, 2004.
44. K. Reivelt. World Year of Physics in Estonia. Preparatory meeting of
European Physical Society on WYP2005, Mulhouse, France, Oct. 4,
2004.
45. I. Renge. Lennard-Jones model of disorder in solids. 4th Intern. Conf. on
Advanced Optical Materials and Devices (AOMD-4), Tartu, Estonia,
July 6–9, 2004.
46. I. Renge. Lennard-Jones approach to inhomogeneous broadening in glasses.
High Resolution Site Selective spectroscopy, Intern. Conf. in Memory
of Roman Personov, Bayreuth, Germany, July 15–18, 2004.
47. M. Saal. Viies element. Eesti XXVI füüsikaõpetajate päevad, Tartu,
24.märts, 2004.
48. P. Saari. Localized waves and relativity. Progress in electromagnetic
research symposium, PIERS’04, Pisa, Italy, March 28–31, 2004
(invited paper).
49. P. Saari. Infotehnoloogia tulevik – kas à la Marx või Malthus, Fukuyama
või Huntington? ITT foorumi, Pärnu, Sept. 16–17, 2004 (invited
paper).
50. P. Saari. Localized waves in ultrafast optics. Seminar of the Max-BornInstitut für Nichlineare Optik und Kurzzeitsspektroskopie, Berlin,
Germany, July 7, 2004 (invited paper).
51. P. Saari. Kuivõrd lokaliseeritav on footon ruumis? Spektroskoopiaseminar, TÜFI, Tartu, Sept. 9, 2004.
52. P. Saari. Teadmistepõhine või ignorantsusepõhine Eesti? Ettekanne Tartu
Rotary klubis, Tartu, Nov. 24, 2004.
53. A. Sherman. Spectral and magnetic properties of the t-J model of cuprate
perovskites. Workshop “Modelling and Simulation in Molecular
Systems, Mesoscopic Structures, and Material Science”, Chemnitz,
Germany, April 21–23, 2004 (invited paper).
54. A. Sherman, M. Schreiber. Resonance peak and incommensurability in
cuprate perovskites. 2nd Euro-Asian Symposium “Trends in Magnetism” (EASTMAG-2004), Krasnoyarsk, Russia, August 24–27, 2004.
55. A. Sherman. Magnetic properties of cuprate perovskites. NATO Advance
Research Workshop “Smart Materials for Ranging Systems”,
Krasnoyarsk, Russia, Aug. 29–Sept. 1, 2004 (invited paper).
162 • Biannual Report 2004/2005
56. I. Sildos, V. Kiisk, S. Lange, J. Aarik, M. Kirm. Photoluminescence of
RE-doped thin metal oxide films. XIIth Feofilov Symp., Ekaterinburg,
Russia, Sept. 22–25, 2004.
57. S. Zazubovich, Y. Usuki, I. Sildos, M. Nikl, A. Krasnikov, V. Kiisk,
N. Senguttuvan, P. Bohacek. Red emission of PbWO4 crystals. XXXIV
Eesti Füüsikapäevad, Tartu, Estonia, Febr. 13–14, 2004 (invited
paper).
POSTER PRESENTATIONS 2004
58. J. Aarik, T. Tätte, V. Kiisk, S. Lange, I. Sildos. Põhiainelt lisanditsentrile toimuva energiaülekande spektroskoopilised uuringud haruldaste
muldmetallidega dopeeritud metalloksiidkiledes ja fiibrites. XXXIV Eesti
Füüsikapäevad, Tartu, Eesti, 13.–14.veebr. 2004.
59. J. Aarik, V. Bitševin, I. Jõgi, H. Käämbre, M. Laan, V. Sammelselg.
Tunnelvoolud kilepakettides. XXXIV Eesti Füüsikapäevad, Tartu, Eesti,
13.–14.veebr. 2004.
60. J. Aarik, A. Kasikov, M. Kirm, S. Lange, T. Uustare, H. Mändar.
Optical properties of crystalline Al2O3 thin films grown by atomic layer
deposition. 4th Intern. Conf. on Advanced Optical Materials and
Devices (AOMD-4), Tartu, Estonia, July 6–9, 2004.
61. J. Aarik, I. Jõgi, K. Kukli, H. Käämbre, M. Laan. Conduction mechanisms in metal-dielectric-metal structures. ALD2004, Helsinki, Finland,
Aug. 16–18, 2004.
62. R. Aceves, P. Perez Salas, T. M. Piters, S. Zazubovich. Self-trapped
exciton luminescence and reabsorption in KI:Eu2+ crystals. 15th Intern.
Conf. on Defects in Insulating Materials (ICDIM-2004), Riga, Latvia,
July 11–16, 2004.
63. P. Adamson. Characteristic reflection angles of nanoscopic layered media
and optical probing of ultrathin dielectric films. 4th Intern. Conf. on
Advanced Optical Materials and Devices (AOMD-4), Tartu, Estonia,
July 6–9, 2004.
64. A. Agui, S. Butorin, T. Käämbre, C. Såthe, T. Saitoh, Y Moritomo,
J Nordgren. Resonant O Ka Emission Spectroscopy of double layered
Manganite La1.2Sr1.8Mn2O7. The 14th Intern. Conf. on Vacuum
Ultraviolet Radiation Physics, Cairns, Australia, July 19–23, 2004.
Talks and Posters at Conferences • 163
65. T. Avarmaa, T. Jantson, H. Mändar, T. Uustare, R. Jaaniso. Nanocrystalline Cr2O3-TiO2 thin films by pulsed laser deposition. E-MRS 2004
Fall Meeting, Warsaw, Poland, Sept. 6–10, 2004.
66. V. Babin, K. Blazek, A. Krasnikov, K. Nejezchleb, M. Nikl,
T. Savikhina, S. Zazubovich. Luminescence of undoped LuAG and YAG
crystals. 15th Intern. Conf. on Defects in Insulating Materials
(ICDIM-2004), Riga, Latvia, July 11–16, 2004.
67. G. Benedek, V. Hizhnyakov. The Role of Defect-Induced Phonon
Localization in Quantum Diffusion. 15th Intern. Conf. on Defects in
Insulating Materials (ICDIM–2004), Riga, Latvia, July 11–16, 2004.
68. P. Bohacek, P. Fabeni, A. Krasnikov, M. Nikl, G. P. Pazzi, C. Susini,
S. Zazubovich. Defects creation under UV-irradiation of PbWO4 crystals.
14th Intern. Conf. on Solid State Dosimetry (SSD14), Yale Univ.,
New Haven, USA, June 27-July 2, 2004.
69. P. Bohacek, P. Fabeni, A. Krasnikov, M. Nikl, G. P. Pazzi, C. Susini,
S. Zazubovich. Defects in UV-irradiated PbWO4:Mo crystals monitored
by TSL measurements. 15th Intern. Conf. on Defects in Insulating
Materials (ICDIM-2004), Riga, Latvia, July 11–16, 2004.
70. S. Dolgov, A. Kärkkänen, T. Kärner, A. Maaroos. Low-temperature (4295 K) thermoluminescence of pure and doped MgO and CaO single
crystals. 15th Intern. Conf. on Defects in Insulating Materials
(ICDIM-2004), Riga, Latvia, July 11–16, 2004.
71. C. Glover, M. Agåker, T. Käämbre, T. Schmitt, M. Adell, L. Ilver,
J. Kanski, L. Kjeldgaard, and J. E. Rubensson. Localized 3d excitations
in Ge, GaAs, and GaN, populated in inelastic soft X-ray scattering,
resonantly enhanced at the 3p edges. The 14th Intern. Conf. on Vacuum
Ultraviolet Radiation Physics, Cairns, Australia, July 19–23, 2004.
72. C. Glover, T. Käämbre, M. Agaker, L. Gridneva, T. Balasubramanian,
J. Andersen, J. E. Rubensson. Effects of momentum conservation in
resonant inelastic soft X-ray scattering in the bulk and at the surface of Be
metal. The 14th Intern. Conf. on Vacuum Ultraviolet Radiation
Physics, Cairns, Australia, July 19–23, 2004.
73. V. Hizhnyakov, J. Kikas, J. Takahashi, A. Laisaar, A. Suisalu,
An. Kuznetsov. Low-energy excitations in glasses under high pressure:
isothermal and cycling effects. 11th Intern. Conf. on Phonon Scattering
in Condensed Matter (Phonons 2004), St.Petersburg, Russia, July 25–
30, 2004.
164 • Biannual Report 2004/2005
74. V. Hizhnyakov, J. Kikas, J. Takahashi, A. Laisaar, A. Suisalu,
An. Kuznetsov. Two-level systems in glasses under high pressure:
temperature cycling effect. 11th Intern. Conf. on Phonon Scattering in
Condensed Matter (Phonons 2004), St. Petersburg, Russia, July 25–
30, 2004.
75. V. Issahanyan, T. Kärner, A. Maaroos, S. Nakonechnyi. Spin relaxation processes in the defect hole centres of Be doped MgO single crystals.
15th Intern. Conf. on Defects in Insulating Materials (ICDIM-2004),
Riga, Latvia, July 11–16, 2004.
76. E. Jalviste, N. Ohta. Electric field induced reorientation of polar molecules in a poly(methyl methacrylate) film studied by electroabsorption
spectroscopy. 4th Intern. Conf. on Advanced Optical Materials and
Devices (AOMD-4), Tartu, Estonia, July 6–9, 2004.
77. V. Kiisk, I. Sildos, S. Lange, V. Reedo, T. Tätte, M. Kirm, J. Aarik.
Photoluminescence characterization of pure and Sm3+–doped thin metal
oxide films. E-MRS 2004, Strasbourg, France, May 24–28, 2004.
78. A. Kikas, T. Käämbre, A. Saar, K. Kooser, E. Nõmmiste, I. Martinson. Resonant Inelastic X-ray Scattering at the K edge of oxygen and
fuorine in insulators. The 14th Intern. Conf. on Vacuum Ultraviolet
Radiation Physics, Cairns, Australia, July 19–23, 2004.
79. A. Kikas, J. Aarik, T. Käämbre, V. Kisand, A. Zakharov, V. Sammelselg, I. Martinson. An X-ray photoabsorption and photoelectron
spectroscopy study of ZrO2 and HfO2 films prepared by atomic layer
deposition. Meeting of the NORFA financed network “Synchrotronbased electron spectroscopy”, Tartu, Estonia, March 15, 2004.
80. P. Konsin, B. Sorkin. A Gigantic Photoinduced dielectric constant of
quantum paraelectric perovskite oxides under a weak electric field in the
electron-lattice theory. 7th European Conf. on Application of Polar
Dielectrics (ECAPD7), Liberec, Czech Republic, September 6–9,
2004.
81. P. Konsin, B. Sorkin. Generalized multiple gap model for the superconductivity in MgB2. 4th Intern. Conf. Nanoscale Heterogeneity and
Quantum Phenomena in Complex Matter (Stripes and Superconductivity, Stripes04), Rome, Italy, September 26 – October 2,
2004.
82. M. Korshunov, S. Ovchinnikov, A. Sherman. Effective Hamiltonian
and the properties of normal and superconducting phases of n-type cuprates.
Talks and Posters at Conferences • 165
83.
84.
85.
86.
87.
88.
89.
90.
91.
92.
Intern. Conf. on Strongly Correlated Electron Systems, Karlsruhe,
Germany, July 26–30, 2004.
A. Kotlov, S. Dolgov, E. Feldbach, L. Jönsson, M. Kirm, A. Lushchik,
V. Nagirnyi, G. Svensson, B. Zadneprovki. Exciton and recombination
luminescence of Al2(WO4)3 crystals. 15th Intern. Conf. on Defects in
Insulating Materials (ICDIM-2004), Riga, Latvia, July 11–16, 2004.
A. Krasnikov, M. Nikl, A. Stolovits, Y. Usuki, S. Zazubovich. Luminescence of the PbWO4:5% Cd crystal. 15th Intern. Conf. on Defects in
Insulating Materials (ICDIM-2004), Riga, Latvia, July 11–16, 2004.
P. Kuusk, M. Saal. A cosmological model for a two-brane world. 17th
Intern. Conf. on General Relatively and Gravitation, Dublin, Ireland,
July 18–23, 2004.
T. Kärner, A. Maaroos, S. Nakonechnyi. EPR spectra of the defect
centres created by neutron irradiation in MgO. 15th Intern. Conf. on
Defects in Insulating Materials (ICDIM-2004), Riga, Latvia, July 11–
16, 2004.
A. Lõhmus. Cryogenic Cleaning of SPM Tips. Nordic-Baltic SPM 2004
workshop, Trondheim, Norway, June 16–19, 2004.
R. Lõhmus. AFM characterization of surface morphology of severe plastic
deformed copper. 3rd ESF Nanotribology Workshop, Sesimbra, Portugal, Sept. 18–24, 2004.
R. Lõhmus. AFM characterization of the surface morphology of the severe
plastic deformed copper. Nordic-Baltic SPM 2004 Workshop, Trondheim, Norway, June 16–19, 2004.
R. Lõhmus. In situ transformations of gold contacts studied by molecular
dynamics simulations. Intern. Conf. on Nanotechnology
(NANOTECH 2004), Boston, USA, March 7–11, 2004.
D. Di Martino, A. Krasnikov, M. Nikl, K. Nitsch, A. Vedda, S. Zazubovich. The 3.83 eV luminescence of Gd/enriched phosphate glasses. 15th
Intern. Conf. on Defects in Insulating Materials (ICDIM-2004), Riga,
Latvia, July 11–16, 2004.
K. Mauring, V. Krasnenko, A. Tkaczyk, E. Tkaczyk, Ö. Farkas. Molecular vibrations of green fluorescent protein. 5th Intern. Conf. on
Biological Physics (ICBP 2004), Göteborg, Sweden, Aug. 23–27,
2004.
166 • Biannual Report 2004/2005
93. K. Mauring, V. Krasnenko, A. Tkaczyk, E. Tkaczyk, Ö. Farkas. Properties of green fluorescent protein determined by molecular vibrations.
SIMU-2004 – Bridging the Scales, Genua, Italy, Aug. 29–31, 2004.
94. A. Niilisk,
J. Aarik,
T. Uustare,
H. Mändar,
S. Tkachev,
M. H. Manghnani. Structural study of ZrO2 and HfO2 thin films grown
by atomic layer deposition. 4th Intern. Conf. on Advanced Optical
Materials and Devices (AOMD-4), Tartu, Estonia, July 6–9, 2004.
95. E. Nõmmiste, V. Kisand, E. Kukk, A. Calo, H. Aksela, S. Aksela.
Photoexcitation, -ionization and fragmentation of molecular rubidium
halides. The 14th Intern. Conf. on Vacuum Ultraviolet Radiation
Physics, Cairns, Australia, July 19–23, 2004.
96. E. Nõmmiste, V. Kisand, M. Hirsimäki, M. Valden, E. Kukk,
T. Käämbre, R. Ruus, A. Kikas. Studying insulator monolayers on metal
substrate. Meeting of the NORFA financed network “Synchrotronbased electron spectroscopy”, Tartu, Estonia, March 15, 2004.
97. V. Peet, S. Shchemeljov. Coherent wave-mixing processes and multiphoton ionization in spatially incoherent conical laser beams. 28th
European Conf. on Laser Interaction with Matter, Rome, Italy, Sept.
6–10, 2004.
98. V. Peet, S. Shchemeljov. Four-wave mixing in spatially incoherent laser
beams. XXXIV Eesti Füüsikapäevad, Tartu, Eesti, Feb. 13–14, 2004.
99. R. Rammula, J. Aarik, A. Kikas, T. Käämbre, V. Sammelselg. AFM
and XPS studies of ultrathin HfO2 films prepared by ALD. 5th NordicBaltic Scanning Probe Microscopy Workshop, Trondheim, Norway,
June 16–19, 2004.
100. R. Rammula, J. Aarik, A. Kikas, T. Käämbre, V. Sammelselg.
Nucleation of HfO2 films deposited by chloride and iodide ALD process.
ALD2004, Helsinki, Finland, August 16–18, 2004.
101. K. Realo, R. Koch, M. Lust, A. Uljas, E. Realo. Lead-210 in air and
surface soil in NE Estonia. 11th Intern. Congress of Intern. Radiation
Protection Association (IRPA), Madrid, Spain, 23–28 May, 2004.
102. K. Rebane. Requirements to impurity activated solis as materials for
optical data storage and processing . 4th Intern. Conf. on Advanced
Optical Materials and Devices (AOMD-4), Tartu, Estonia, July 6–9,
2004.
103. V. Reedo, S. Lange, V. Kiisk, T. Tätte, I. Sildos. Influence of ambient
gas to the photoluminescence of rare-earth ions in sol-gel derived metal
Talks and Posters at Conferences • 167
104.
105.
106.
107.
108.
109.
110.
111.
112.
113.
oxide films. 4th Intern. Conf. on Advanced Optical Materials and
Devices (AOMD-4), Tartu, Estonia, July 6–9, 2004.
P. Rubin, A. Sherman. Magnetic properties of the 2D Heisenberg model
on a triangular lattice. 30th Intern. Winter School-Symposium of
theorists “Kourovka-2004”, Kyshtym, Russia, Feb. 22–28, 2004.
R. Ruus, K. Kooser, E. Nõmmiste, A. Saar, I. Martinson, A. Kikas.
Potential barrier effects in Cs 3d resonance photoemission of CsF. Meeting
of the NORFA financed network “Synchrotron-based electron
spectroscopy”, Tartu, Estonia, March 15, 2004.
R. Ruus. A crystal-field calculation program for ionic solids and molecules.
Synchrotron Radiation Summer School, Kääriku, Estonia, June 2–4,
2004.
K. Saal, M. Plaado, T. Tätte. Aminofunktsionaalsete sool-geelkilede
valmistamine ja rakendused biotehnoloogias. XXXIV Eesti Füüsikapäevad, Tartu, Estonia, 13.–14.veebr. 2004.
V. Sammelselg, J. Aarik, A. Kikas, R. Rammula, T. Käämbre,
K. Kooser, J. Lu, K. Kukli. XPS investigation of ultrathin ALD films and
interface layers. ALD2004, Helsinki, Finland, August 16–18, 2004.
F. Savikhin, M. Kerikmäe, E. Feldbach, A. Lushchik, D. Onishchik,
D. Rakhimov, I.Tokbergenov. Fast intrinsic emission with the participation of oxyanion and cation excitations in metal sulphates. 15th
Intern. Conf. on Defects in Insulating Materials (ICDIM-2004), Riga,
Latvia, July 11–16, 2004.
M. Selg, P. Miidla. Solution of quantum-mechanical inverse problem
based on complete knowledge of the phase shift. 8th European Conf. on
Atomic and Molecular Physics (ECAMP VIII), Rennes, France, July
6–10, 2004.
A. Sherman, M. Schreiber. Resonance peak and incommensurability in
cuprate perovskites. 20th General Conf. of Condensed Matter Division
of European Phys. Society, Prague, Czech Republic, July 19–23, 2004.
I. Sildos, V. Kiisk, S. Lange, J. Aarik, M. Kirm. Photoluminescence of
RE-doped thin metal oxide films. 15th Intern. Conf. on Defects in
Insulating Materials (ICDIM-2004), Riga, Latvia, July 11–16, 2004.
A. Stolovits, R. K. Kremer, H. Mattausch, A. Sherman, A. Simon.
Quantum interference of electrons in Nb5Te4. 20th General Conf. of
Condensed Matter Division of European Phys. Society, Prague, Czech
Republic, July 19–23, 2004.
168 • Biannual Report 2004/2005
114. A. Tarre, A. Rosental, T. Uustare, A. Kasikov. SnO2 on sapphire:
amorphous, polycrystalline and epitaxial films. 4th Intern. Conf. on
Advanced Optical Materials and Devices (AOMD-4), Tartu, Estonia,
July 6–9, 2004.
115. A. Tarre, J. Harjuoja, A. Aidla, T. Uustare, J. Aarik, A. Rosental,
L. Niinistö. Comparison of atomic layer deposition of SnO2 from SnI4 and
O2 on different substrates. ALD2004, Helsinki, Finland, August 16–18,
2004.
116. I. Tehver. Calculation of CARS excitation spectrum by transform method.
15th Intern. Conf. on Defects in Insulating Materials (ICDIM-2004),
Riga, Latvia, July 11–16, 2004.
117. I. Tehver. Calculation of CARS excitation profile of ZnPc: manifestation
of Herzberg-Teller interaction. 11th Intern. Conf. on Phonon Scattering
in Condensed Matter (Phonons 2004), St. Petersburg, Russia, July 25–
30, 2004.
118. K. Timpmann, M. Rätsep, A. Freiberg. Emitting excitonic polaron states
in core LH1 and peripheral LH2 bacterial light-harvesting complexes.
14th Intern. Congress on Photobiology, Jeju, Korea, June 10–15,
2004.
119. G. Trinkunas, A. Freiberg. Abrupt exciton self-trapping in finite and
disordered one-dimensional aggregates. EXCON '04 6th Intern. Conf.
on Excitonic Processes in Condensed Matter, Krakow, Poland, July 6–
9, 2004.
120. E. Vasil’chenko, I. Kudryavtseva, A. Lushchik, Ch. Lushchik,
V. Nagirnyi. Selective creation of colour centres and peaks of thermally
stimulated luminescence by VUV photons in LiF single crystals. 15th
Intern. Conf. on Defects in Insulating Materials (ICDIM-2004), Riga,
Latvia, July 11–16, 2004.
121. P. Vois, A. Suisalu, An. Kuznetsov, R. Jaaniso, H. Bill. Characterization of Sm2+ centers in Ba12F19Cl5–xBrx crystals by 5D0–7F0 luminescence
and spectral hole burning. 4th Intern. Conf. on Advanced Optical
Materials and Devices (AOMD-4), Tartu, Estonia, July 6–9, 2004.
122. A. Voloshinovskii, I. Pashuk, G. Struganyuk, S. Zazubovich. Chargetransfer luminescence processes. 15th Intern. Conf. on Defects in
Insulating Materials (ICDIM-2004), Riga, Latvia, July 11–16, 2004.
Talks and Posters at Conferences • 169
ORAL PRESENTATIONS 2005
123. J. Aarik, A. Rosental, A. Tarre. Atomic layer deposition of nanostructured
materials for microelectronic and sensoric applications. National Conf. of
Network for Nanostructured Materials of ACC on Nanopowders,
Nanostructured Materials and Coatings, Tallinn, Estonia, March 17,
2005.
124. J. Aarik. Aatomkihtsadestamine: alusuuringutest rakendusteni. XXXV
Eesti Füüsikapäevad, Tartu, 22.–23. märts, 2005 (invited paper).
125. V. Babin, M. Kink, Y. Maksimov, K. Nejezchleb, M. Nikl, S. Zazubovich. VUV spectroscopy of Sc3+ and Ce3+ doped LuAG crystals. Intern.
Conf. “Vacuum Ultraviolet Spectroscopy and Interaction with
Condensed Matter” (VUV 2005), Irkutsk, Russia, July 18–22, 2005.
126. V. Babin, M. Kink, Y. Maksimov, K. Nejezchleb, M. Nikl, S. Zazubovich. Luminescence of undoped and Ce3+-doped Lu(Sc,Y)AG crystals.
14th Intern. Conf. on Luminescence (ICL’05), Beijing, China, July
25–29, 2005.
127. A. Freiberg, M. Rätsep, K. Timpmann, G. Trinkunas. Band structure,
static disorder, and electron-lattice coupling distinguishing photosynthetic
antenna excitons. Intern. Conf. on Luminescence, Peking, China, July
25–29, 2005.
128. A. Freiberg. The antenna polarons. Intern. Conf. on Luminescence,
Institute of Physics, Chinese Academy of Sciences, Peking, China, July
27, 2005 (invited paper).
129. A. Freiberg, M. Rätsep, K. Timpmann, G. Trinkunas. Band structure
and dynamics of photosynthetic antenna excitons. 15th Intern. Conf. on
Dynamical Processes in Excited States of Solids, Shanghai, China, Aug.
1–5, 2005.
130. A. Freiberg. Miks on metsad rohelised? TÜMRI ja Eesti Biokeskuse
aastakonverents 2005, Tartu, 14.–15. dets. 2005.
131. G. Gerasimov, R. Hallin, B. Krylov, A. Treshchalov, A. Morozov,
A. Lissovski, G. Zwereva, A. Arnesen. The intense VUV narrow band
emission from an inert gas mixture discharge. VII Intern. Conf. on
Atomic and Molecular Pulsed Lasers, Tomsk, Russia, Sept. 12–16,
2005 (invited paper).
132. I. Jõgi, J. Aarik, K. Kukli, H. Käämbre, M. Laan, J. Lu, T. Sajavaara,
T. Uustare. The effect of precursors on the structure and conductivity of
170 • Biannual Report 2004/2005
133.
134.
135.
136.
137.
138.
139.
140.
141.
142.
143.
144.
145.
atomic layer deposited TiO2 films. Fifteenth Euoropean Conf. on
Chemical Vapor Deposition (EUROCVD-15), Bochum, Germany,
Sept. 4–9, 2005.
L. Järv. Entroopia, elu ja (füüsikaline) eshatoloogia. Molekulaarbioloogia
talvekool, Kääriku, 4.–6. veebr. 2005 (invited paper).
L. Järv. Silmapaistvat viimase aasta teoreetilises alusfüüsikas. TÜ
Suveülikooli raames toimunud füüsikaõpetajate seminar-konverents
“Füüsika õpetamise probleemid”, Tartu, 28. juuni 2005 (invited
paper).
L. Järv. Kujutlusvõime laboratoorium: mõtteeksperimendid füüsikas.
Teaduse ja religiooni kolleegiumi II kevadkool “Loodus, kultuur,
kujutlusvõime”, Põltsamaa, 22.–23. aprill 2005 (invited paper).
L. Järv. Varp-masinate lahendid üldrelatiivsusteoorias. TÜ teoreetilise
füüsika seminar, Tartu, 6. dets. 2005.
L. Järv. Stringiteooria kompaktifitseerimine ja kiirenevalt paisuv Universum. TÜ teoreetilise füüsika seminar, Tartu, 29. märts 2005.
L. Järv. Stringiteooria alternatiivuniversumite “maastik”. TÜ teoreetilise
füüsika seminar, Tartu, 15. märts 2005.
L. Järv. Kõrgemat järku kalibratsiooniteooriatest. TÜ teoreetilise füüsika
seminar, Tartu, 8. märts 2005.
L. Järv. Tume energia ja maailma lõpp. TÜ teoreetilise füüsika seminar,
Tartu, 1. märts 2005.
L. Järv. Accelerating Universe and Moduli Stabilisation from String
Theory Compactifications. HIP String and QFT group weekly Journal
Club, Helsinki, Finland, Feb. 14, 2005.
L. Järv. Creation and decay of X-ray excitations in ionic solids. NordForsk
Network Meeting “Synchrotron-based Electron Spectroscopy”,
Aalborg and Rebild Bakker, Denmark, April 25–26, 2005.
A. Kasikov. Dependence of the obtained thin film optical parameters on a
computing procedure. 13th Intern. Congress on Thin Films
ICTF13/ACSIN8, Stockholm, Sweden, June 19–23, 2005.
M. Kiisk. Tritium depths profile measurements in inner wall tiles from
ASDEX-Upgrade, JET and TFTR. Estonian-Finnish Fusion Collaboration Seminar, Tallinn, Dec. 8, 2005 (invited paper).
M. Kirm, J. Aarik, E. Feldbach, S. Lange, H. Mändar, T. Uustare.
Luminescence spectroscopy of thin oxide films grown by atomic layer
Talks and Posters at Conferences • 171
146.
147.
148.
149.
150.
151.
152.
153.
154.
155.
deposition. 207th Meeting of Electrochemical society, Quebec City,
Canada, May 13–20, 2005.
M. Kirm, V. Babin, V. Nagirnyi, N. Shiran, V. Voronova, V. Nesterkina, K. Shimamura, K. Kitamura, E. Villora. Spectroscopic investigations of fluoride based scintillating materials. Intern. Conf. on
Inorganic Scintillators and their Industrial Applications (SCINT2005),
Alushta, Ukraine, Sept. 19–23, 2005.
A. Krasnikov, M. Nikl, S. Zazubovich. Processes resulting in thermal
quenching of the blue emission in PbWO4 crystals. Intern. Conf. on
Inorganic Scintillators and their Industrial Applications (SCINT2005),
Alushta, Ukraine, Sept. 19–23, 2005.
N. Kristoffel. Free energy functional and critical magnetic fields
anisotropy in MgB2. NATO Adv. Res. Workshop on Electron
Correlation in New Materials and Nanosystems, Yalta, Ukraine, Sept.
19–23, 2005 (invited paper).
K. Kukli, S. Duenas, H. Castan, H. Carcia, J. Barbolla, J. Aarik,
A. Aidla, M. Ritala, M. Leskelä. Struktuuri korrastamatus ja keelutsoonisiseste elektronlõksude tihedus kõrge dielektrilise läbitavusega tahkiskihtides. XXXV Eesti Füüsikapäevad, Tartu, 22.–23. märts 2005.
P. Kuusk. Relatiivsusteooria esimene sajand. Eesti filosoofia aastakonverents “Filosoofia võimus ja võimutus”, Tartu, 26.–28. mai 2005.
P. Kuusk. Kaasaegse kosmoloogia standardmudel. Molekulaarbioloogia
talvekool, Kääriku, 4.–6. veebr. 2005 (invited paper).
P. Kuusk. Einsteini ja teiste murrangulised artiklid imepärastel aastatel
1904–1908. EFS noorte füüsikute VII sügiskool, Kääriku, 28.–30. okt.
2005 (invited paper).
T. Käämbre. Participator RIXS in BeO. NordForsk Network Meeting
“Synchrotron-based Electron Spectroscopy”, Aalborg and Rebild
Bakker, Denmark, April 25–26, 2005.
S. Lange, V. Kiisk, V. Reedo, M. Kirm, J. Aarik, I. Sildos. Luminescence of rare earth ions in metal-oxide thin films and its applications.
1st Intern. Workshop on Photoluminescence in Rare Earts: Photonics
Materials and Devices (PRE’05), Trento, Italy, May 2–3, 2005.
A. Lushchik, Ch. Lushchik. Role of hot electrons and hot holes in the
process of defect creation and luminescence excitation by VUV radiation in
wide-gap dielectrics. 13th Intern. Conf. on Radiation Effects in
172 • Biannual Report 2004/2005
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157.
158.
159.
160.
161.
162.
163.
164.
165.
Insulators (REI-2005), Santa Fe, New Mexico, USA, Aug. 28–
Sept. 02, 2005.
A. Lushchik. Estonia (New countries without contract of Association).
Intern. Workshop “Enlargement of the European Union: Integration
of New and Recent Partners in the EURATOM Fusion Programme”,
Garching, Germany, Sept. 12–13, 2005.
A. Lushchik. Estonian Intern. collaboration in fusion investigations.
Intern. Conf. on Fusion Investigations in Lithuania and Neighbouring
Countries, Vilnius, Lithuania, Dec. 1, 2005.
M. Lust, E. Realo. Radioecology in Estonia – developments. NKS-B
Summary Seminar (with focus on radioecology and measurement
techniques), Tartu, Estonia, Oct. 24–25, 2005 (invited paper).
V. Nagirnyi. Conduction band structure in oxyanionic crystals. Intern.
Conf. on Inorganic Scintillators and their Industrial Applications
(SCINT2005), Alushta, Ukraine, Sept. 19–23, 2005.
A. Niilisk, J. Aarik, S.N. Tkachev, M.H. Mangnani. Õhukeste
oksiidkilede Ramani ja Brillouini hajumine. XXXV Eesti Füüsikapäevad,
Tartu, 22.–23. märts 2005.
A. Niilisk, M. Moppel, M. Pärs, I. Sildos, T. Avarmaa, R. Jaaniso,
J. Aarik. Structural study of technologically important oxide thin films by
micro-Raman spectroscopy. Conf. on Knowledge-based Materials and
Technologies for Sustainable Chemistry (MTSC), Tallinn, Estonia,
June 1–5, 2005.
M. Nikl, A. Yoshikawa, T. Fukuda, A. Krasnikov, A. Vedda,
K. Nejezchleb. Pr3+-doped novel single crystal scintillators. Intern. Conf.
on Inorganic Scintillators and their Industrial Applications
(SCINT2005), Alushta, Ukraine, Sept. 19–23, 2005 (invited paper).
V. Reedo, M. Järvekülg, S. Lange, T. Tätte. Uniform aminosiloxane
films for immobilization of biomolecules: a sol-gel approach. Nanopowders, Nanostructured Materials and Coatings, Tallinn, Estonia,
March 17, 2005.
M. Saal. Looduslik valik Multiversumis ehk universumite looduslik valik.
Molekulaarbioloogia talvekool, Kääriku, 4.–6. veebr. 2005 (invited
paper).
M. Saal. Lokaalne Universum:kas eriline koht. Von Krahli Akadeemia,
Tallinn, 22. mai 2005 (invited paper).
Talks and Posters at Conferences • 173
166. M. Saal. Braanikosmoloogia ehk lühike lugu sellest, kuidas seletada Univesumi kiirenevat paisumist ja vältida algset singulaarsust. TÜ Suveülikooli raames toimunud füüsikaõpetajate seminar-konverents “Füüsika õpetamise probleemid”, Tartu, 28. juuni 2005 (invited paper).
167. M. Saal. Braanikosmoloogiast. Teadus ja religioon: Algused ja lõpud,
USUS 02.075, Tartu, 23.märts 2005 (invited paper).
168. M. Saal. Erirelatiivsusteooria matemaatiline taust. Astronoomiahuviliste
10. üle-Eesti kokkutulek, Kaali, 10–15. aug. 2005 (invited paper).
169. P. Saari. How small a packet of photons can be made? 14th Intern. Laser
Physics Workshop, LPHYS’05, Kyoto, Japan, July 4–8, 2005 (invited
paper).
170. P. Saari. Füüsika ja turvalilisus. Akadeemiline loeng (a) TA-s, (b) TÜ
aulas, (a) Tallinnas, (b) Tartu, (a) 30. märts; (b) 12. mai 2005.
171. P. Saari. How small a packet of photons can be made? Workshop on
Classical and Quantum Interference, Olomouc, Czech Republic, Oct.
29–30, 2005 (invited paper).
172. A. Sherman. Incommensurate spin dynamics in underdoped cuprate
perovskites. 2nd Workshop on Functional Materials, Athens, Greece,
Sept. 25–30, 2005 (invited paper).
173. A. Stolovits, K. Ahn, R. K. Kremer, A. Sherman. Quantum interference
of electrons in fibrous Ta4Te4Si. Conf. on Nanopowders, Nanostructured Materials and Coatings, Tallinn, Estonia, March 17, 2005.
174. A. Stolovits, R. K. Kremer, Hj. Mattausch, J.R. O'Brien, H. Okudera,
X-M. Ren, A. Sherman, A. Simon. Quantum interference in Nb5–x Te4.
Intern. Conf. on Transport in Interacting and Disordered Systems
/(TIDS 11), Egmond aan Zee, The Netherlands, Aug. 21–26, 2005.
175. S. Zazubovich, A. Krasnikov, M. Nikl. Disintegration of exciton and
defect states in PbWO4:MO,Ce crystal. Intern. Conf. on Inorganic
Scintillators and their Industrial Applications (SCINT2005), Alushta,
Ukraine, Sept. 19–23, 2005.
176. T. Tamm, J. Linnanto, A. Ellervee, A. Freiberg. Modeling of pessure
effects on absorption spectra of solvated chlorophyll and bacteriochlorophyll
molecules. Intern. Conf. Computational Methods in Science and
Engineering 2005 (ICCMSE 2005), Loutraki, Greece, Oct. 21–26,
2005.
177. A. Treshchalov, A. Lissovski. VUV-VIS spectroscopic diagnostics of highcurrent pulsed volume discharge in argon. VII Intern. Conf. On Atomic
174 • Biannual Report 2004/2005
and Molecular Pulsed Lasers, Tomsk, Russia, Sept. 12–16, 2005
(invited paper).
POSTER PRESENTATIONS 2005
178. L. Aarik, M. Kiisk. Samblike kasutamine bioindikaatoritena keskkonnadosimeetrias. XXV Eesti Füüsikapäevad, Tartu, 22.–23. märts 2005.
179. S. Dziarzhytski, E. Jalviste, F. Temps. Hydrogen-bonded self and water
complexes of 1H-indazole. Bunsentagung 2005, Frankfurt, Germany,
May 5–7, 2005.
180. A. Ellervee, J. Linnanto, T. Tamm, A. Freiberg. Solvent effects on
chlorophyll and bacteriochlorophyll molecules studied by high pressuretuning spectroscopy. “Physics of Life” Workshop in Biological Physics,
Copenhagen, Denmark, Aug. 21–27, 2005.
181. V. Fedoseyev. Reflection and refraction of a light beam carrying the
orbital angular momentum: dynamical aspects. Intern. Conf. on
Coherent and nonlinear Optics (ICONO-2005), St. Petersburg,
Russia, May 11–15, 2005.
182. E. Feldbach, A. Kotlov, I. Kudryavtseva, P. Liblik, A. Lushchik,
Ch. Lushchik, A. Maaroos, V. Nagirnyi, E. Vasil’chenko. Lowtemperature irradiation effects in lithium ortosilicate. 13th Intern. Conf.
on Radiation Effects in Insulators (REI-2005), Santa Fe, New Mexico,
USA, Aug. 28–Sept. 02, 2005.
183. E. Feldbach, J. Aarik, M. Kirm, P. Liblik, H. Mändar. Spectroscopic
diagnostics of defects and traps in thin scintillating films of hafnia. Intern.
Conf. on Inorganic Scintillators and their Industrial Applications
(SCINT2005), Alushta, Ukraine, Sept. 19–23, 2005.
184. A. Floren, I. Kärkkänen, T. Avarmaa, R. Jaaniso. Luminescence decay
in oxygen sensor materials: a general model of quenching with distributed
rate constants. Eurosensors XIX, Barcelona, Spain, Sept. 11–14, 2005.
185. M. Haas. Dynamical beats of synchrotron radiation as a nuclear polariton
effect. ICAME’05, Intern. Conf. on the Appl. of the Mössbauer Effect,
Montpellier, France, Sept. 5–9, 2005.
186. V. Hizhnyakov, G. Benedek, I. Tehver, V. Boltrushko. Electronic
transitions between dynamically stable and weakly unstable states: Optical
spectra of molecules trapped in superfluid 4He droplets. AIOM2005: First
Talks and Posters at Conferences • 175
187.
188.
189.
190.
191.
192.
193.
194.
195.
Conf. on Advances in Optical Materials, Tucson, USA, Oct. 12–15,
2005.
V. Hizhnyakov, V. Boltrushko, I. Tehver. Optical transitions in centres
with soft dynamics in the excited state. PIPT2005: Second Intern. Conf.
on Photo-Induced Phase Transitions: Cooperative, Non-Linear and
Functional Properties, Rennes, France, May 24–28, 2005.
V. Hizhnyakov. Resonance two-quantum emission by a medium with
oscillating in time optical length. PIPT2005: Second Intern. Conf. on
Photo-Induced Phase Transitions: Cooperative, Non-Linear and
Functional Properties, Rennes, France, May 24–28, 2005.
I. Jõgi, M. Laan, K. Kukli, J. Aarik. Lähteainete mõju aatomkihtsadestatud TiO2 kilede juhtivusele. XXXV Eesti Füüsikapäevad, Tartu,
22.–23. märts 2005.
M. Järvekülg, V. Reedo, S. Lange, U. Mäeorg. Low-dimentional HfO2
structures elaborated by sol-gel technique. TNT2005, Oviedo, Spain,
Aug. 29–Sept. 02, 2005.
M. Kirm, A. Gektin, V. Nagirnyi, V. Nesterkina, K. Shimamura,
N. Shiran, E. Villora. VUV spectroscopy of Ca0,65Eu0,35F2,35 single crystal.
Intern. Conf. “Vacuum Ultraviolet Spectroscopy and Interaction with
Condensed Matter” (VUV 2005), Irkutsk, Russia, July 18–22, 2005.
V. Kisand, E. Nõmmiste, E. Kukk, A. Caló, H. Aksela, S. Aksela.
Fragmentation and electronic decay of vacuum ultraviolet-excited resonant
states of molecular rubidium halides. Intern. Workshop on Photoionization, Campinas, Brazil, July 27–31, 2005.
P. Konsin, B. Sorkin. Off-center displacements of Ti ions in oxide
ferroelectrics and a gigantic photo-induced dielectric constant of quantum
paraelectric perovskite oxides in the electron-lattice theory. Second
Internat. Conf. on “Photo-Induced Phase Transitions; Cooperative,
Non-Linear and Functional Properties” (PIPT 2005), Rennes, France,
May 24–28, 2005.
P. Konsin, B. Sorkin. Doping dependence of the coherence length in the
two-component model for La2–xSrxCuO4 thin films. Workshop on Weak
Superconductivity (WWS’05), Bratislava, Slovak Republic, Sept. 16–
19, 2005.
K. Kooser, A. Kikas, V. Kisand, T. Käämbre, A. Saar, E. Nõmmiste,
I. Martinson. Resonant Inelastic X-ray Scattering at the K edge of oxygen
and fluorine in insulators. NordForsk Network Meeting “Synchrotron-
176 • Biannual Report 2004/2005
196.
197.
198.
199.
200.
201.
202.
203.
204.
based Electron Spectroscopy”, Aalborg and Rebild Bakker, Denmark,
April 25–26, 2005.
K. Kooser, A. Kikas, V. Kisand, T. Käämbre, E. Nõmmiste, I. Martinson. Participator RIXS in BeO. 18th Annual Meeting of Organisation for Users of Synchrotron Radiation at MAX-lab, Lund, Sweden,
Sept. 28–29, 2005.
K. Kooser, A. Kikas, T. Käämbre, V. Kisand, E. Nõmmiste, I. Martinson. Participator RIXS at Be 1s-edge in BeO. Nordic and European
Summer School in Synchrotron Radiation Science “New perspectives
and new sources for XUV- and X-ray Science”, Röstanga and Lund,
Sweden, June 13–21, 2005.
A. Krasnikov, M. Nikl, S. Zazubovich. Defects creation under UV
irradiation of lead tungstate crystals. Intern. Conf. of Physics Students
(ICPS’2005), Coimbra, Portugal, Aug. 11–18, 2005.
A. Krasnikov, M. Nikl, S. Zazubovich. Spectroscopy of excitons in lead
tungstates. IV Intern. Conf. for Students, Young Scientists and
Engineers “Optics’2005”, St.Petersburg, Russia, Oct. 17–21, 2005.
N. Kristoffel, T. Örd, P. Rubin. Doping dependence of cuprate in-plane
coherence length in a two-component model. IV Intern. Conf. “Vortex
Matter in Nanostructured Superconductors”, Crete, Greece, Sept. 3–9,
2005.
N. Kristoffel. Coherence in a two-component superconductor and doping
dependence of cuprate properties. NATO Adv. Res. Workshop ElectronCorrelation in New Materials and Nanosystems, Yalta, Ukraine, Sept.
19–23, 2005.
K. Kukli, M. Ritala, M. Leskelä, J. Lu, J. Aarik, A. Hårsta. Atomic layer
deposition of nanocrystalline metal oxide dielectric films. Finnish
Chemical Congress, Helsinki, Finland, April 26–28, 2005.
K. Kukli, M. Ritala, M. Leskelä, J. Lu, J. Aarik, A. Hårsta. Atomic layer
deposition of nanocrystalline hafnium oxide dielectric films. Fifteenth
Euoropean Conf. on Chemical Vapor Deposition (EUROCVD-15),
Bochum, Germany, Sept. 4–9, 2005.
An. Kuznetsov, U. Visk, A. Suisalu, A. Laisaar, J. Kikas, A. Osvet,
A. Winnacker. Temperature and pressure dependence of the homogeneous
width of 7F0–5D0 electronic transition in Sm2+-doped sodium borate glass.
14th Intern. Conf. on Luminescence (ICL’05), Beijing, China, July
25–29, 2005.
Talks and Posters at Conferences • 177
205. A. Laisaar, A. Suisalu, An. Kuznetsov, J. Kikas. High-pressure lowtemperature spectroscopy of pyrene molecules in commensurate and
incommensurate phases of biphenyl. Joint 20th AIRAPT-43rd EHPRG
Intern. Conf. on High Pressure Science and Technology, Karlsruhe,
Germany, June 27–July 1, 2005.
206. A. Lissovski, A. Treshchalov. Kinetics of VUV-VIS spontaneous emission
of high-current pulsed volume discharge in argon. VII Intern. Conf. On
Atomic and Molecular Pulsed Lasers, Tomsk, Russia, Sept. 12–16, 2005.
207. A. Lissovski, A. Treshchalov. Kinetics of Ar2* emission in high-pressure
pulsed discharge. Intern. Student Conf. Development in Optics and
Photonics DOP-2005, Riga, Latvia, Apr. 30–May 1, 2005.
208. A. Lissovski, A. Treshchalov. Saturation of Ar2* VUV emission output
with increase of the pumping power in Ar high-pressure pulsed discharge.
XXXV Eesti Füüsikapäevad, Tartu, March 22–23, 2005.
209. V. N. Makhov, M. Kirm, G.Zimmerer. Intrinsic luminescence of CsF.
Intern. Conf. on Inorganic Scintillators and their Industrial Applications (SCINT2005), Alushta, Ukraine, Sept. 19–23, 2005.
210. K. Mauring, V. Krasnenko, S. Miller. Photophysics of the blue
fluorescent protein. 14th Intern. Conf. on Luminescence (ICL’05),
Beijing, China, July 25–29, 2005.
211. S. Neicheva, N. Shiran, M. Kirm, M. Weber, K. Shimamura. Intrinsic
scintillations in LiCaAlF6 crystals. Intern. Conf. on Inorganic
Scintillators and their Industrial Applications (SCINT2005), Alushta,
Ukraine, Sept. 19–23, 2005.
212. E. Nõmmiste, V. Kisand, E. Kukk, A. Calo, H. Aksela, S. Aksela.
Photoexcitation, -ionization and fragmentation of molecular rubidium
halides. NordForsk Network Meeting “Synchrotron-based Electron
Spectroscopy”, Aalborg and Rebild Bakker, Denmark, April 25–26,
2005.
213. I. Ots, H. Uibo, H. Liivat, R.-K. Loide, R. Saar. Transversely polarized
beams and Z boson spin orientation in e+e– o 2 with anomalous ZZ and
ZJJ couplings. The XXII Intern. Symposium on Lepton-Photon
Interactions , Uppsala, Sweden, June 30–July 5, 2005.
214. V. Palm, N. Palm. Terrylene-doped biphenyl monocrystals for singlemolecule optical spectroscopy. 20th Congress of the Intern. Commission
for Optics (ICO XX): Challenging Optics in Science & Technology,
Changchun, China, Aug. 21–26, 2005.
178 • Biannual Report 2004/2005
215. V. Palm, N. Palm, J. Kikas. Terrylene-doped biphenyl monocrystals for
single-molecule spectroscopy. 11th Intern. Workshop on “Single Molecule Spectroscopy and Ultra Sensitive Analysis in the Life Sciences”,
Berlin, Germany, Sept. 21–23, 2005.
216. V. Peet, S. Shchemeljov. Sum-frequency generation and multiphoton
ionization in spatially incoherent conical laser beams. XXXV Eesti
Füüsikapäevad , Tartu, March 22–23, 2005 .
217. H. Pettai, V. Oja, A. Laisk, A. Freiberg. The red edge of the photosynthetic activity in green plants is at 780 nm. Gordon Conf., New
Hampshire, USA, July, 2005 .
218. M. Pärs, V. Palm, J. Kikas. Selective spectroscopy of terrylene in
incommensurate matrix of biphenyl. 14th Intern. Conf. on Luminescence (ICL’05), Beijing, China, July 25–29, 2005.
219. M. Pärs, V. Palm, N. Palm, J. Kikas. Single-molecule spectroscopy study
of terrylene-activated monocrystalline biphenyl. Winter School in
Theoretical Chemistry (“Nanophotonics”), Helsinki, Finland, Dec. 7–
9, 2005.
220. I. Rebane, R. Koch. Calculations of changes in spontaneous emission rate
of a single impurity molecule in dependence on the direction of the
transition dipole moment in uniaxial host crystals. 14th Intern. Conf. on
Luminescence (ICL’05), Beijing, China, July 25–29, 2005.
221. I. Rebane. Different values of spontaneous emission rate of a singleimpurity molecule of pentacene in biaxial p-terphenyl crystal. 14th Intern.
Conf. on Luminescence (ICL’05), Beijing, China, July 25–29, 2005.
222. V. Reedo, M. Järvekülg, S. Lange, U. Mäeorg. Preparation of lowdimentional HfO2, HfO2 and HfO2 structures by sol-gel technigue. 29th
Estonian chemistry days, Tallinn, Estonia, Oct. 20–21, 2005.
223. V. Reedo, M. Järvekülg, S. Lange, T. Tätte. Preparation of lowdimentional HfO2, HfO2 and HfO2 structures by sol-gel technigue.
Advanced Nanotechnologies, Testing, Production and Application of
Nanoscale Materials, Primorsko, Bulgaria, June 1–7, 2005.
224. M. Saal, L. Järv, P. Kuusk. Models of the Kanno-Soda Type Brane
Cosmology. Intern. Seminar „From strings to cosmic web”, Gröningen,
Holland, Nov. 30–Dec. 2, 2005.
225. K. Saal, M. Plaado, I. Kink, A. Kurg, V. Kiisk, J. Kozevnikova, Aminopropyl embedded silica films as potent substrates in DNA microarray
Talks and Posters at Conferences • 179
226.
227.
228.
229.
230.
231.
232.
233.
234.
235.
applications. MRS Spring Meeting, San Francisco, USA, March 28 –
Apr. 1, 2005.
M. Selg. Reference potential approach to the inverse problem in quantum
mechanics. The Nineteenth Colloquium on High Resolution Molecular
Spectroscopy, Salamanca, Spain, Sept. 11–16, 2005.
M. Selg. Uniform Treatment of the First and the Second Emission
Continua of Rare Gases. 14th Intern. Conf. on Luminescence (ICL’05),
Beijing, China, July 25–29, 2005.
S. Shchemeljov, V. Peet. Multiphoton processes in spatially incoherent
conical laser beams. IV Intern. Young Scientist Conf. “Optics–2005”,
S.-Petersburg, Russia, Oct.17–21, 2005.
A. Sherman. Incommensurate spin dynamics in underdoped cuprate
perovskites. Intern. Conf. Strongly Correlated Electron Systems,
Vienna, Austria, July 26–30, 2005.
A. Sherman, M. Schreiber. Incommensurate spin dynamics in underdoped cuprate perovskites. 69. Jahrestagung der Deutschen Physikalischen Gesellschaft, Berlin, Germany, March 4–9, 2005.
A. Stolovits, Y. Usuki, S. Zazubovich, A. Krasnikov, M. Nikl.
Luminescence of the PbWO4:5% Cd crystal. XXXV Eesti Füüsikapäevad,
Tartu, Estonia, March 22–23, 2005.
I. Tehver. Excitation profile of CARS in multimode systems in the case of
femtosecond excitation. AIOM2005: First Conf. on Advances in Optical
Materials, Tucson, USA, Oct. 12–15, 2005.
A. Treshchalov, A. Lissovski. Dye laser absorption probing of highcurrent pulsed volume discharge in argon. VII Intern. Conf. On Atomic
and Molecular Pulsed Lasers, Tomsk, Russia, Sept. 12–16, 2005.
T. Tätte, V. Jacobsen, M. Paalo, R. Branscheid, M. Kreiter, U. Maeorg, K. Saal, A. Lõhmus, I. Kink. Preparation of Sb doped SnO2 SPM
tips and their use as transparent probes in STM induced light hybrid
microscopy. NSTI Nanotechnology Conf. and Trade Show, Anaheim,
CA, USA, May 8–12, 2005.
T. Örd, N. Kristoffel, K. Rägo. Free energy functional and critical
magnetic fields of a two-gap superconductor with intra- and interband
interactions. IV Intern. Conf. “Vortex Matter in Nanostructural
Superconductors”, Crete, Greece, Sept. 3–9, 2005.
7. DISSERTATIONS PREPARED
AT THE INSTITUTE
A. Kotlov, Dielectric oxyanionic crystals: band structure and electronic
excitations (PhD, solid state physics). Supervisors Dr. V. Nagirnyi (Inst.
of Physics, UT) and Prof. A.Lushchik (Inst. of Physics and Inst. of
Materials Science, UT), Referees Dr. Vl. Makhov (Lebedev Physical
Inst., Moscow) and Dr. R. Kink (Inst. of Physics, UT); maintained at
the UT, 20.10.2004.
M. Saal, Studies of pre-big bang and braneworld cosmology (PhD, theoretical
physics). Supervisor Dr. Piret Kuusk (Inst. of Physics, UT), Referees
Dr. S. Räsänen (Oxford Univ.) and Dr. E. Saar (Tartu Observatory);
maintained at the UT, 03.11.2004.
E. Gershkevich, Dose to bone marrow and leukaemia risk in external beam
radiotherapy of prostate cancer (PhD, applied physics). Supervisors Prof.
K.R.Trott (Univ. of London, Queen Mary’s College) and Dr. E. Realo
(Inst. of Physics, UT), Referees Prof. W.Dörr (Technical Univ. of
Dresden) and Dr. Vl. Shcherbakov (North-Estonian Regional
Hospital); maintained at the UT, 06.06.2005.
V. Boltrushko, Theory of vibronic transitions between states with hard and soft
local phonon dynamics (MSc, theoretical physics). Supervisor Dr. V.
Hizhnyakov; maintained at the UT, 09.06.2004.
V. Issakhanyan, Virtual EPR spectrometer and its use on the example of
MgO:Be crystal (MSc, solid state physics). Supervisors Prof L.Pung and
Dr. E. Feldbach; maintained at the UT, 09.06.2004.
V. Krasnenko, Photophysics of green and blue fluorescent proteins (MSc, solid
state physics). Supervisor Dr. K. Mauring; maintained at the UT,
29.06.2004.
Dissertations Prepared at the Institute • 181
A. Lissovski, Spectroscopic diagnostics of pulsed discharge in high-pressure
rare gas mixtures (MSc, optics and spectroscopy). Supervisor
Dr. A. Treshchalov; maintained at the UT, 29.06.2004.
M. Pärs, Confocal microscopy for detection of single emission centres (MSc,
solid state physics). Supervisor Dr. V. Palm; maintained at the UT,
09.06.2004.
K. Õige, Optimisation of oxygen-sensitive layer for fibre-optical sensor (MSc,
physical and analytical chemistry). Supervisors Dr. A. Suisalu and Dr.
T. Avarmaa; maintained at the UT, 04.06.2004.
A. Floren, Stability and heterogenity of oxygen sensitivity in polymer films
doped with Pd-porphyrins (MSc, optics and spectroscopy). Supervisor
Dr. R. Jaaniso; maintained at the UT, 08.06.2005.
A. Kärkkänen, Photo-induced changes in electrical conductivity of carbon
nanotube films in different gas environments (MSc, solid state physics).
Supervisor Dr. R. Jaaniso; maintained at the UT, 08.06.2005.
I. Kärkkänen, Processes of electronic energy transfer in OLED materials based
on polyvinylcarbazole (MSc, optics and spectroscopy). Supervisor
Dr. R. Jaaniso; maintained at the UT, 08.06.2005.
S. Lange, Rare-earth ions in metal oxide films: investigation of photoexcitation
mechanisms (MSc, solid state physics). Supervisor Dr. I. Sildos;
maintained at the UT, 08.06.2005.
R. Rammula, Atomic layer deposition study of HfO2 thin films (MSc, solid
state physics). Supervisors J. Aarik and Prof. V.Sammelselg; maintained
at the UT, 08.06.2005.
8. GRADUATION THESES PREPARED
AT THE INSTITUTE
L. Aarik, Gamma spectrometric analysis of radionuclides in lichens and soils in
Tartu (BSc). Supervisor Dr. E. Realo, 2004.
S. Burak, Implementation and testing of electronic registration system for highresolution Fabry-Perot interferometer (BSc). Supervisors Dr. V. Palm and
M. Pärs, 2004.
K. Isakar, Monte Carlo method for evaluation of self-attenuation correction
factors in 210Pb gamma spectrometry (BSc). Supervisor Dr. E. Realo,
2004.
M. Kleeman, Humidity reaction in optical polymer films (BSc). Supervisors
Prof J. Kikas and Dr. A. Suisalu, 2004.
A. Ruudi, Luminescence quenching by oxygen in polystyrene films activated with
Pd-tetraphenylporphyrine: dual gas transport and two-centre model (BSc).
Supervisors Dr. R. Jaaniso and Dr. T. Avarmaa, 2004.
H. Valtna, Focused X wave as highly localized non-diffracting light pulse (BSc).
Supervisors Prof. P. Saari and Dr. K. Reivelt, 2004.
I. Bljahhin, Construction of optical diffraction masks (BSc). Supervisor
Dr. H. Mändar, 2005.
L. Feklistova, Magnetical and optical information storages and interfaces (BSc).
Supervisor Dr. E. Nõmmiste, 2005.
S. Galayev, Spectral transformers for display panels (PDP) (BSc). Supervisors
Prof. A. Lushchik and Dr. A. Maaroos, 2005.
S. Hödemann, Light scattering in tempered glass (BSc). Supervisors
Dr. A. Suisalu and Prof. J. Kikas, 2005.
M. Järvekülg, Preparation of hafnia materials from hafnium4butoxide by solgel (BSc). Supervisors V. Reedo and Dr. U. Mäeorg, 2005.
A. Jürgenson, The Christiansen filter (BSc). Supervisors Prof. J. Kikas and
Dr. A. Suisalu, 2005.
Graduation Theses Prepared at the Institute • 183
K. Kasemets, Organically modified titanium oxide films as substrates for
immobilization of aminated DNA (BSc). Supervisors S. Mäeorg and
K. Saal, 2005.
M. Kodu, Laser deposition of PbZrO3 and SrRuO3 thin films (BSc). Supervisor
Dr. R. Jaaniso, 2005.
S. Leinberg, High vacuum AFM: problems and solutions (BSc). Supervisor
Dr. R. Lõhmus.
A. Lukner, Influence of ambient gaseous environment to the impurities emission
in Sm3+-doped TiO2 thin films: possible use in gas sensing (BSc).
Supervisors V. Kiisk and Dr. I. Sildos, 2005.
S. Miller, Properties of the excited states of the blue fluorescent protein (BSc).
Supervisor Dr. K. Mauring, 2005.
M. Moppel, Development of confocal microscope for Raman and luminescence
measurements (BSc). Supervisors M. Pärs and Dr. I. Sildos, 2005.
R. Pärna, Atomic layer deposition of chromium(III)oxide thin films (BSc).
Supervisors Dr. A. Niilisk, A. Tarre and Dr. A. Rosental, 2005.
A. Ragni, Using of interface card NI6259 in physical experiments (BSc).
Supervisor Dr. E. Nõmmiste, 2005.
R. Sarakvasha, Properties of electronic excitations in CdWO4:Mo and CdMoO4
crystals (BSc). Supervisors Dr. V. Nagirnyi and Dr. A. Kotlov, 2005.
M. Tamm, Luminescence study of TiO2 thin films doped with Eu3+ and
Er3+ ions (BSc). Supervisors S. Lange and Dr. I. Sildos, 2005.
M. Timusk, Indoor gamma dose (BSc). Supervisor Dr. E. Realo, 2005.
U. Visk, Phase and energy relaxation of electron transition 7F0–5D0 of Sm2+ ion
(BSc). Supervisor Dr. A. Suisalu, 2005.
9. SCIENTIFIC MEETINGS ORGANIZED
International Meeting of the NORFA financed network “Synchrotron-based
electron spectroscopy”; Tartu, Estonia, March 15, 2004; 20 participants
from Estonia, Norway, Sweden and Denmark. Organizing – A. Kikas.
International Synchrotron Radiation Summer School; Kääriku, Estonia,
June 2–5, 2004; 39 participants from Estonia, Finland, Sweden and
Hungary. Organizing Committee – E. Nõmmiste (Inst. of Physics, UT) and
E. Kukk (Univ. of Turku).
4th International Conference on Advanced Optical Materials and Devices
(AOMD-4); Tartu, Estonia, July 7–10, 2004; 95 participants from Estonia,
Finland, France, Germany, Israel, Latvia, Lithuania, Poland, Russia, Sweden
and USA. Organizing Committee – A. Gerst, R. Jaaniso, A. Rosental,
I. Sildos, L. Sildos, A. Tarre, I. Tehver.
15th International Conference on Insulating Materials (ICDIM-2004); Riga,
Latvia, July 11–16, 2004; 235 participants from 30 countries. Organized
together with Institute of Solid State Physics, Univ. of Latvia. Members of
Organizing Committee from Institute of Physics – A. Lushchik (cochairman), T. Kärner, V. Nagirnyi and S. Zazubovich. Guest Editors of
Materials ICDIM-2004 (Phys. status solidi (c)) – A. Lushchik,
S. Zazubovich and I. Tale.
6th Young Physicist’s Autumn School, organized by the Estonian Physical
Society; Kääriku, Estonia, Oct. 8–10, 2004; 65 participants. Organizing
Committee – M. Saal, A. Hektor, A. Kikas.
Scientific Meetings Organized • 185
7th Young Physicist’s Autumn School, organized by the Estonian Physical
Society; Kääriku, Estonia, Oct. 28–30, 2005; 87 participants. Organizing
Committee – A. Hektor, A. Kuusk, M. Müntel, K. Reivelt, M. Saal.
Exhibition in nuclear fusion “Expo Fusion”; Tartu, Estonia, Nov. 8–14,
2005; about 5000 visitors; Tallinn, Estonia, Nov. 21–28, 2005; about 3000
visitors. Main organizer – M. Kiisk.
10. VISITS TO RESEARCH
CENTRES ABROAD
2004
A. Aabloo – French Atomic Energy Agency (France), 26.04.–30.04.04.
A. Anijalg, – University of Latvia (Latvia9, 20.07.–22.07.04.
S. Dolgov – Lund University, MAX-Lab (Sweden), 08.02.–16.02.04,
07.11.–21.11.04.
E. Feldbach – Lund University, MAX-Lab (Sweden), 08.02.–16.02.04,
07.11.–21.11.04.
A. Freiberg – Institute of Physics, Vilnius (Lithuania), 14.11.–20.11.04.
M. Haas – University of Luebeck, Institute of Physics (Germany), 22.11.–
17.12.04.
V. Hizhnyakov – University of Milan, University of Bicocca (Italy), 02.02.–
17.02.04, 22.02.–11.03.04.
V. Hizhnyakov – University of Stuttgart, Dept. of Theoretical Physics
(Germany), 17.02.–22.02.04.
V. Hizhnyakov – Max-Planck Institute, Göttingen, Brandenburg Technical
University (Germany), 26.10.–31.10.04.
V. Hizhnyakov – Brussels University (Belgium), 28.11.–01.12.04.
R. Jaaniso – University of Latvia, Institute of Solid State Physics (Latvia)
E. Jalviste – University of Kiel, Institute of Physical Chemistry (Germany),
04.09.–30.12.04.
M. Kiisk – Studsvik Ltd. (Sweden), 09.11.–12.11.04.
A. Kikas – Lund University, MAX-Lab (Sweden), 01.02.–08.02.04, 15.02.–
23.02.04.
A. Kikas –Mulhouse (France), 25.03.–28.03.04.
A. Kikas – University of Hamburg, HASYLAB (Germany), 18.05.–
26.05.04.
Visits to Research Centres Abroad • 187
M. Kirm – University of Hamburg, HASYLAB (Germany), 31.05.–
07.06.04, 03.12.–13.12.04.
M. Kirm – University of Latvia, Institute of Solid State Physics (Latvia),
20.10.–21.10.04.
M. Kirm – BESSY, Berlin (Germany), 31.10.–07.11.04.
V. Kisand – Lund University, MAX-Lab (Sweden), 25.01.–09.02.04,
15.02.–24.02.04, 19.05.–24.05.04, 27.06.–05.07.04, 11.10.–
18.10.04.
V. Kisand – University of Hamburg, HASYLAB (Germany), 18.04.–
29.04.04, 18.05.–26.05.04.
V. Kisand – BESSY, Berlin (Germany), 31.10.–07.11.04.
K. Kooser – Lund University, MAX-Lab (Sweden), 01.02.–08.02.04,
15.02.–23.02.04, 11.10.–18.10.04.
K. Kooser – University of Aarhus (Denmark), 18.10.–07.11.04.
A. Kotlov – University of Hamburg, HASYLAB (Germany), 25.01.–
02.02.04, 31.05.–07.06.04, 08.12.–15.12.04.
A. Kotlov – Lund University (Sweden), 07.11.–21.11.04.
A. Krasnikov – Institute of Physics, Acad. Sci. of Czech Republic (Czech
Republic), 06.09.04.–06.01.05.
T. Käämbre – Lund University, MAX-Lab (Sweden), 26.01.–31.01.04,
01.02.–08.02.04, 15.02.–23.02.04, 12.04.–18.04.04, 20.05.–
30.05.04, 25.06.–29.06.04, 27.07.–31.07.04, 06.09.–10.09.04,
11.10.–18.10.04, 15.11.–26.11.04, 13.12.–17.12.04.
T. Käämbre – University of Hamburg, HASYLAB (Germany), 18.05.–
26.05.04.
S. Lange – University of Hamburg, HASYLAB (Germany), 26.04.–
02.05.04.
A. Lukner – University of Hamburg, HASYLAB (Germany), 26.04.–
02.05.04.
A. Lushchik – University of Hamburg, HASYLAB (Germany), 25.01.–
02.02.04, 31.05.–07.06.04, 08.12.–15.12.04.
A. Lushchik – University of Latvia, Institute of Solid State Physics (Latvia),
14.04.–16.04.04.
A. Lushchik – St.Petersburg State Technological University, Vavilov GOI
Science Center (Russia), 18.11.–23.11.04.
Ch. Lushchik – St.Petersburg State University, Physical-Technical Institute
(Russia), 20.11.–24.11.04.
188 • Biannual Report 2004/2005
A. Lõhmus – Soome, Helsinki University of Technology (Finland), 18.02.–
20.02.04.
A. Lõhmus – Helsinki University of Technology (Finland), 11.08.–
13.08.04.
A. Lõhmus – University of Latvia, Institute of Physics (Latvia), 27.05.2004.
A. Lõhmus – Brussels (Belgium), 26.06.–29.06.04.
A. Lõhmus – University of Latvia, Institute of Chemical Physics (Latvia),
31.08.2004.
A. Lõhmus – University of Latvia, Institute of Chemical Physics (Latvia),
18.11.04, 29.12.04.
R. Lõhmus – University of Latvia, Institute of Physics (Latvia), 03.02.–
04.02.04.
R. Lõhmus – University of Latvia, Institute of Physics (Latvia), 27.05.2004.
R. Lõhmus – Lund University, MAX-Lab and Chalmers University
(Sweden), University of Trondheim, Dept. of Applied Physics
(Norway), 11.06.–21.06.04.
R. Lõhmus – University of Latvia, Institute of Chemical Physics (Latvia),
18.11.2004.
M. Moppel – University of Uppsala, Department of Chemistry (Sweden),
06.12.–12.12.04.
H. Mändar – University of Konstanz, Laboratory of Solid State Chemistry
(Germany), 21.09.–24.20.04.
V. Nagirnyi – University of Hamburg, HASYLAB (Germany), 25.01.–
02.02.04, 31.05.–07.06.04, 08.12.–15.12.04.
V. Nagirnyi – Rootsi, Lund University, MAX-Lab (Sweden), 08.02.–
16.02.04, 07.11.–21.11.04.
V. Nagirnyi – University of Latvia, Institute of Solid State Physics (Latvia),
28.06.–29.06.04.
V. Nagirnyi – Institute of Solid State Physics and Optics (Hungary),
13.09.–26.09.04.
E. Nõmmiste – Lund University, MAX-Lab (Sweden), 25.01.–09.02.04.
E. Nõmmiste – Prague (Czech Republic), 22.05.–27.05.04.
E. Nõmmiste – University of Latvia, Institute of Solid State Physics (Latvia),
20.10.–21.10.04.
E. Nõmmiste – University of Oulu (Finland), 21.10.–23.10.04.
M. Pärs – University of Uppsala, Department of Chemistry (Sweden),
20.09.–27.09.04, 06.12.–12.12.04.
Visits to Research Centres Abroad • 189
E. Realo – London (Great Britain), 28.06.2004.
E. Realo – Paris (France), 20.10.–24.10.04.
E. Realo – Brussels (Belgium), 11.02.–13.02.04, 26.04.–28.04.04,
30.06.04.
K. Rebane – University of St.Petersburg (Russia), 20.05.–27.05.04.
K. Rebane – University of Stuttgart (Germany), 31.10.–05.11.04.
K. Reivelt – Max-Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Berlin (Germany), 04.07.–08.07.04.
K. Reivelt – Mulhouse (France), 14.10.–17.10.04.
R. Ruus – University of Oulu (Finland), 06.06.–03.07.04.
K. Saal – Lund University, Chalmers University, University of Trondheim,
MAX-Lab, Dept. of Applied Physics (Sweden Norway), 11.06.–
21.06.04.
P. Saari – Max-Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Berlin (Germany), 04.07.–08.07.04.
I. Sildos – University of Erlangen, University of Regensburg, Institute of
Materials Research, Institute of Physics (Germany), 03.02.–11.02.04.
I. Sildos – Institute of General Physics, Moscow (Russia), 28.09.–06.10.04.
A. Stolovits – Max-Planck Institute for Solid State Research (Germany),
06.09.–02.12.04.
A. Sherman – Technical University of Chemnitz, Institute of Theoretical
Physics (Germany), 24.06.–03.08.04.
S. Zazubovich – Institute of Physics, Czech Acad. Sci., Laboratory of Luminescence (Czech Republic), 06.09.–19.09.04.
S. Zazubovich – Institute of Applied Physics, Laboratory of Laser Spectroscopy (Italy), 25.09.03.–24.03.04.
A. Tarre – University of Uppsala, The Ångström Laboratory (Sweden),
20.09.–03.10.04.
A. Treshchalov – Institute of Thermonuclear Research, Moscow (Russia),
14.06.–19.06.04.
2005
V. Babin – University of Hamburg, DESY, HASYLAB (Germany), 21.01.–
31.01.05; 25.02.–07.03.05; 08.06.–22.06.05; 24.10.–02.11.05;
12.12.–14.12.05.
190 • Biannual Report 2004/2005
V. Babin – Institute of Geochemistry, Russian Acad. Sci. (Russia), 17.07.–
28.07.05.
V. Babin – University of Utrecht, Department of Condensed Matter and
Interfaces (The Netherlands), 17.05.–22.05.05.
V. Babin – Philips Research (The Netherlands), 21.08.–25.08.05.
V. Boltrushko – University of St.Petersburg, (Russia), 20.11.–29.11.05.
V. Boltrushko – University of Helsinki, Dept. of Chemistry (Finland),
06.12.–09.12.05.
E. Feldbach – Lund University, MAX-Lab (Sweden), 20.02.–27.02.05.
E. Feldbach – University of Hamburg, DESY, HASYLAB (Germany),
28.02.–07.03.05; 06.06.–17.06.05; 18.07.–25.07.05; 12.12.–14.12.05
E. Feldbach – The Saclay Laser-Matter Interaction Center (France), 04.10.–
20.10.05.
A. Freiberg – Umeå University (Sweden), 12.06.–16.06.05.
V. Hizhnyakov – Cornell University (USA), 19.03.–26.03.05.
V. Hizhnyakov – University of Brussels, INTAS (Belgium), 08.03.–
11.03.05; 15.11.–19.11.05
K. Isakar – European Physical Society, (France), 12.01.–16.01.05.
K. Isakar – Institute for Transuranium Elements (Germany), 14.06.–
18.06.05.
K. Isakar – CERN (Switzerland), 24.05.–28.05.05.
K. Isakar – Jozef Stefan Institute (Slovenia), 13.09.–19.09.05.
V. Issakhanyan – University College London (Great Britain), 09.05.–
08.07.05.
L. Järv – Helsinki Institute of Physics (Finland), 13.02.–17.02.05.
L. Järv – Institute of Adv. Studies (Israel), 27.12.05–09.01.06.
T. Käämbre – University of Hamburg, DESY, HASYLAB (Germany),
13.02.–21.02.05;
T. Käämbre – Lund University, MAX-Lab (Sweden), 06.02.–12.02.05;
20.11.–24.11.05; 05.12.–19.12.05.
H. Kaasik – University of Helsinki, Dept. of Chemistry (Finland), 06.12.–
10.12.05.
M. Kiisk – Institute for Transuranium Elements (Germany), 14.06.–
18.06.05.
M. Kiisk – Jozef Stefan Institute (Slovenia), 13.09.–19.09.05.
V. Kiisk – Ångström Laboratory (Sweden), 09.10.–14.10.05.
Visits to Research Centres Abroad • 191
A. Kikas – University of Hamburg, DESY, HASYLAB (Germany), 06.02.–
14.02.05;
A. Kikas – Lund University, MAX-Lab (Sweden), 15.02.–21.02.05; 13.04.–
18.04.05; 13.06.–20.06.05; 27.09.–30.09.05.
A. Kikas – Aalborg University (Denmark), 24.04.–27.04.05.
I. Kink – Lund University, MAX-Lab (Sweden), 07.02.–12.02.05.15.03.–
16.03.05;
I. Kink – European Commission (Belgium), 17.02.–19.02.05; 18.05.–
20.05.05; 10.10.–11.10.05.
I. Kink – HUT (Finland), 08.06.05.
I. Kink – Zernike Group (The Netherlands), 02.05.–15.05.05.
R. Kink – Lund University, MAX-Lab (Sweden), 06.02.–20.02.05.
M. Kirm – University of Hamburg, DESY, HASYLAB (Germany), 28.02.–
07.03.05; 06.06.–22.06.05; 18.07.–22.07.05; 12.12.–14.12.05.
M. Kirm – Consultative Committee for the Euroatom Specific Research and
Training Programme in the field of Nuclear Energy (Fusion, CCE-FU)
(Belgium), 06.06.–07.06.05.
M. Kirm – VDI/DE-IT Innovation + Technik GmbH Dept. Innovation
Europe (Germany), 31.08.–02.09.05; 28.11.–29.11.05.
M. Kirm – The Saclay Laser-Matter Interaction Center (France), 04.10.–
13.10.05.
M. Kirm – CCE-FU, CEA (France), 10.11.–12.11.05.
V. Kisand – Lund University, MAX-Lab (Sweden), 13.02.–20.02.05;
08.05.–23.05.05; 15.06.–27.06.05; 27.09.–30.09.05.
V. Kisand – Aalborg University (Denmark), 24.04.–26.04.05.
V. Kisand – Synchrotron Radiation Center (Brazil), 25.07.–07.08.05.
K. Kooser – University of Hamburg, DESY, HASYLAB (Germany), 06.02.–
12.02.05.
K. Kooser – Lund University, MAX-Lab (Sweden), 13.02.–21.02.05;
08.05.–23.05.05; 13.06.–21.06.05; 14.11.–24.11.05; 07.12.–
19.12.05.
K. Kooser – Aarhus University, Laboratory of Synchrotron Radiation
ASTRID (Denmark), 31.08.–26.09.05.
A. Kotlov – University of Hamburg, DESY, HASYLAB (Germany), 24.01.–
31.01.05; 28.02.–07.03.05; 20.03.–29.03.05; 24.10.–31.10.05.
A. Kotlov – Lund University, MAX-Lab (Sweden), 20.02.–27.02.05;
27.06.–04.07.05.
192 • Biannual Report 2004/2005
S. Lange – University of Hamburg, DESY, HASYLAB (Germany), 28.02.–
07.03.05.
S. Lange – Ångström Laboratory (Sweden), 09.10.–14.10.05; 12.12.–
13.12.05.
A. Lissovski – University of Uppsala, Institute of Physics (Sweden), 26.09.–
08.10.05.
A. Lissovski – Physikzentrum Bad Honnef (Germany), 08.10.–16.10.05.
A. Lõhmus – Acad. Sci. of Ukraine, Institute of Materials Research
(Ukraine), 04.03.–07.03.05.
A. Lõhmus – Helsinki University of Technology (Finland), 07.06.–
08.06.05; 21.06.–22.06.05; 17.08.–18.08.05.
A. Lõhmus – Latvian State University, Institute of Chemical Physics
(Latvia), 12.09.05.
R. Lõhmus – Latvian State University (Latvia), 31.01.05.
R. Lõhmus – Latvian State University, Institute of Chemical Physics
(Latvia), 09.12.–13.12.05.
R. Lõhmus – Zernike Group (The Netherlands), 14.03.–23.03.05; 18.04.–
15.05.05.
R. Lõhmus – Helsinki University of Technology (Finland), 17.11.–
20.11.05.
R. Lõhmus – K-Tek (USA), 08.09.–11.09.05.
A. Lushchik – University of Hamburg, DESY, HASYLAB (Germany),
20.03.–28.03.05; 24.10.–31.10.05.
A. Lushchik – EFDA Meeting (Germany), 11.09.–14.09.05.
A. Moorits – Helsinki University of Technology (Finland), 27.10.–
28.10.05.
M. Moppel – Institute of Physics (Ukraine), 13.06.–17.06.05.
V. Nagirnyi – Lund University, MAX-Lab (Sweden), 20.02.–28.02.05;
27.06.–04.07.05
V. Nagirnyi – Institute for Solid State Physics and Optics, Hungarian Acad.
Sci. (Hungary), 24.04.–01.05.05.
V. Nagirnyi – University of Hamburg, DESY, HASYLAB (Germany),
20.203.–29.03.05; 24.10.–31.10.05.
V. Nagirnyi – The Saclay Laser-Matter Interaction Center (France), 04.10.–
20.10.05.
E. Nõmmiste – Aalborg University (Denmark), 24.04.–27.04.05.
E. Nõmmiste – Finnish Acad. Sci. (Finland)12.01.–13.01.05.
Visits to Research Centres Abroad • 193
E. Nõmmiste – Lund University, MAX-Lab (Sweden), 08.05.–17.05.05;
15.06.–27.06.05; 27.09.–29.09.05; 13.11.–20.11.05.
E. Nõmmiste – University of Turku (Finland), 06.10.–07.10.05.
E. Nõmmiste – Synchrotron Radiation Center (Brazil), 25.07.–07.08.05.
V. Palm – Lund Laser Center (Sweden), 03.04.–14.04.05; 24.04.–05.05.05.
V. Palm – Munich Trade Fairs International (Germany), 14.06.–16.06.05.
M. Pärs – Lund Laser Center (Sweden), 03.04.–14.04.05; 24.04.–05.05.05.
M. Pärs – Helsinki University, Dept. of Chemistry (Finland), 06.12.–
09.12.05.
M. Pärs – Andor Technology (Ireland), 12.12.–15.12.05.
M. Rätsep – Han-Meitner-Institut (Germany), 27.04.–01.05.05.
E. Realo – Consultative Committee for the Euroatom Specific Research and
Training Programme in the field of Nuclear Energy (Fusion, CCE-FU)
(Belgium), 26.01.–28.01.05; 07.03.–09.03.05.
E. Realo – EURATOM Scientific and Technical Committee (STC)
(Belgium), 04.04.–07.04.05.
E. Realo – EUROATOM Scientific and Technical Committee (STC)
(Germany), 23.10.–26.10.05.
K. Rebane – University of Helsinki (Finland), 17.04.–01.05.05.
K. Rebane – Russian Acad. Sci., Ioffe Institute of Physics (Russia), 15.05.–
29.05.05.
K. Rebane – CERN, (Switzerland), University of Stuttgart (Germany),
26.10.–08.11.05.
V. Reedo – NENAMAT Committee (Bulgaria), 31.05.–07.06.05.
R. Ruus – University of Turku (Finland), 01.11.–24.12.05.
M. Saal – Summer School “The Invisible Universe: Dark Matter and Dark
Energy”, Karfas (Greece), 23.09.–05.10.05.
H. Salujärv – Umeå University (Sweden), 14.11.–19.11.05.
A. Sherman – Technical University of Berlin, Technical University of
Chemnitz (Germany), 03.03.–29.03.05; 23.11.–30.11.05.
I. Sildos – University of Regensburg (Germany), 03.05.–08.05.05.
I. Sildos – Institute of Physical Technology (Russia), 28.07.–31.07.05.
I. Sildos – Amsterdam University, Van-der-Waals Institute; Utrecht
University, Debye Institute (The Netherlands), 10.10.–15.10.05.
I. Sildos – Institute of General Physics (Russia), 09.12.–15.12.05.
A. Stolovits – Max Planck Institute for Solid State Research (Germany),
20.06.–01.08.05; 18.08.–13.10.05.
194 • Biannual Report 2004/2005
A. Tarre – ELFA (Sweden), 01.02.–03.03.05.
A. Tarre – Ångström Laboratory (Sweden), 09.10.–17.10.05.
T. Tätte – Adlershof Science Center (Germany), 09.02.–12.02.05.
T. Tätte – University of Padova (Italy), 15.05.–29.05.05.
K. Timpmann – Umeå University (Sweden), 12.06.–16.06.05; 14.11.–
19.11.05.
A. Treshchalov – Uppsala University, Dept. of Physics (Sweden), 25.09.–
07.10.05.
J. Vahi – Helsinki University of Technology (Finland), 27.10.–28.10.05;
07.11.–18.11.05.
A. Vaigu – European Physical Society (France), 12.01.–16.01.2005.
H. Valtna – European Physical Society (France), 12.01.–16.01.2005.
S. Vlassov – Latvian State University, Institute of Chemical Physics (Latvia),
09.12.05.
S. Zazubovich – Institute of Physics, Lab of Luminescence (Czech
Republic), 17.04.–29.204.05.
11. VISITORS
2004
T. H. Andersen – University of Southern Denmark (Denmark), 15.03.04.
E. Arakelova – State Engineering University of Armenia (Armenia), 26.05.–
27.05.04.
A. Beitlerova – Institute of Physics, Acad. Sci. CR, Laboratory of Luminescence (Czech Republic), 19.09.–03.10.04.
J. Bohr – Danish University of Technology (Denmark), 30.09.04.
K. J. Borve – University of Bergen, Dept. of Chemistry (Norway), 15.03.04.
G. Damazyan – State Engineering University of Armenia (Armenia),
26.05.–27.05.04.
B. Green – European Commission (Belgium), 25.10.–26.10.04.
P. Hoyer – University of Helsinki, Faculty of Science, Dept. of Physical
Sciences, High Energy Physics Division (Finland), 25.02.–28.02.04.
S. Karttunen – Association Euroatom-Tekes, VTT Processes (Finland),
13.02.–14.02.04.
A. Kechiantz – State Engineering University of Armenia (Armenia), 26.05.–
27.05.04.
R. Kremer – Max-Planck Institute for Solid State Research, Stuttgart
(Germany), 10.06.–19.06.04.
A. Krumins – University of Latvia, Institute of Solid State Physics (Latvia),
09.12.04.
M. Ladadweh – University of Bergen, Dept. of Chemistry (Norway),
15.03.04.
J. Linnanto – University of Jyväskylä, Dept. of Chemistry (Finland),
03.12.–06.12.04.
E. Mihokova – Institute of Physics, Acad. Sci. CR, Laboratory of Luminescence (Czech Republic), 19.09.–26.09.04.
196 • Biannual Report 2004/2005
N. Mironova – Institute of Solid State Physics, Riga (Latvia), 05.07.–
09.07.04.
J. Onsgaard – Aalborg University, Institute of Physics (Denmark), 15.03.04.
A. Osvet – University of Erlangen, Institute of Materials Science (Germany),
25.03.04.
J. Pieper – Humboldt University (Germany), 07.06.–11.06.04.
V. Pokropivny – Institute for Problems of Materials Science of NAS, Kiev
(Ukraine), 06.08.–05.09.04.
J. Prikulis – University of Latvia, Institute of Chemical Physics (Latvia),
03.10.–06.11.04.
A. Sternberg – University of Latvia, Institute of Solid State Physics (Latvia),
09.12.04.
S. Svensson – University of Uppsala (Sweden), 15.03.04.
E. D. Trifonov – St.Petersburg Pedagogical University (Russia), 13.10.–
16.10.04.
M. Wagner – University of Stuttgart, Institute of Theoretical Physics
(Germany), 29.09.04.
G. Öhrwall – University of Uppsala (Sweden), 15.03.04.
A. Watterich – Institute of Solid State Physics and Optics, Hungarian Acad.
Sci. (Hungary), 16.07.–22.07.04.
2005
S. Aksela – University of Oulu, Lab of Electron Spectroscopy (Finland),
27.12.05.
H. Aksela – University of Oulu, Lab of Electron Spectroscopy (Finland),
27.12.05.
G. Corradi – Institute for Solid State Physics and Optics, Hungarian Acad.
Sci. (Hungary), 29.08.–11.09.05.
D. Ivanov – Institute of Chemistry, Dept. of Surface and Interface (France),
02.06.05.
R. K. Kremer – Max Planck Institute for Solid State Research (Germany),
03.06.–10.06.05.
E. Kukk – University of Oulu, Dept. of Physical Sciences (Finland),
27.12.05.
J. Linnanto – University of Jyväskylä, Dept. of Chemistry (Finland),
21.12.–23.12.05
Visitors • 197
I. Martinson – Lund University (Sweden), 24.11.–27.11.05.
J. Mares – Institute of Physics, Czech Acad. Sci. (Czech Republic), 10.05.–
24.05.05.
A. K. Müller – University of Zürich, Institute of Physics (Switzerland),
05.06.–09.06.05.
J. Nilsson – Hasselblad Foundation (Sweden), 24.11.–26.11.05.
V. Pokropivny – Institute of Materials Research (Ukraine), 06.08.–
20.08.05.
T. Saarsoo – Helsinki Valve and Fitting OY (Finland), 29.12.05.
K. Schwartz – Gesellschaft für Schwerionenforschung (GSI) (Germany),
01.11.–08.11.05.
G. Seibold – Brandenburg Technical University (Germany), 06.06.–
11.06.05.
D. Smith – University of Southhampton, School of Physics and Astronomy
(Great Britain), 28.06.05.
N. Solovieva – Institute of Physics, Czech Acad. Sci. (Czech Republic),
10.05.–24.05.05.
Ch. Söderlund – Vacuumservice OY (Finland), 29.04.05.
A. Zurita – European Commission, DG Research, Directorate J, Energy
Unit J.6 (Belgium), 07.11.–09.11.05.
K. Tanskanen – Kata Electronics OY (Finland), 11.07.–12.07.05.
12. PEDAGOGICAL ACTIVITIES
12.1. Lecture courses at the University of Tartu
J. Aarik – FKMF.01.107 Thin-film technology (obligatory subject, 2 credits;
2004)
J. Aarik – FKMF.01.043 Optoelectronics (elective subject, 2 credits; 2004)
J. Aarik – FKMF.01.044 Technology of electronic devices (elective subject,
1 credit, 2004)
V. Babin, H. Kaasik, A. Tarre – Fundamentals of physical measurements
(obligatory subject, 2 credits; 2005)
A. Freiberg – BGMR.07.023 Biological physics (obligatory subject,
4 credits; 2004, 2005)
V. Hizhnyakov – FKTF.03.006 Quantum mechanics I (obligatory subject,
4.5 credits; 2004, 2005)
V. Hizhnyakov – FKTF.03.017 Fundamentals of quantum mechanics
(obligatory subject, 2 credits; 2005)
V. Hizhnyakov – FKTF.04.012 Theoretical physics (obligatory subject,
4 credits, 2005)
R. Jaaniso – FKMF.01.087 Materials technologies (obligatory subject,
2 credits; 2004)
R. Jaaniso – FKMF.01.110 Physical materials technologies (obligatory
subject, 2 credits; 2004, 2005)
R. Jaaniso – FKMF.01.132 Nanotechnologies (elective subject, 2 credits;
2004, 2005)
A. Kikas – FKMF.02.014 Interaction of ionizing radiation with matter
(elective subject, 2 credits; 2004)
A. Kikas, M. Kirm, T. Kärner – FKEF.01.037 Experimental methods in
materials physics (obligatory subject, 4 credits; 2005)
Pedagogical Activities • 199
R. Kink – Biological effects of the laser light. Types of lasers and fibers.
Lasers in the therapy and surgery (a part of FKEF.02.028 Biomedical
instrumentation and methods, 4 credits) (elective subject; 2004, 2005)
V. Korrovits – FKEF.04.013 Experimental cryoengineering (elective subject,
2 credits; 2004, 2005)
V. Korrovits, A. Kotlov, I. Kudryavtseva, K. Mauring, R. Koch –
FKEF.02.105 Electrical measurements (practical training; obligatory
subject, 2 credits; 2005)
P. Kuusk – ELFI.03.002 – Philosophical fundamentals of natural sciences
(obligatory subject, 2 credits; 2004, 2005)
P. Kuusk – ELFI.03.003 – Philosophy of time and space (selected topics)
(elective and optional subject, 2 credits; 2004, 2005)
T. Kärner – FKEF.02.016 Magnetic resonance methods in materials science
(elective subject, 2 credits; 2005)
A. Lushchik – FKMF.02.013 Dosimetric and scintillation materials (obligatory subject, 2 credits; 2004, 2005)
A. Lushchik – FKMF.02.017 Physics of solid materials (elective subject,
4 credits, 2004)
A. Lushchik – FKEF.01.012 Spectroscopy I (obligatory subject, 1 credit;
2004)
H. Mändar – FKMF.02.001 X-ray diffraction (obligatory subject, 1 credit;
2004, 2005)
H. Mändar – FKMF.02.009 X-ray crystal structure analysis (elective subject,
2 credits; 2004)
H. Mändar – FKMF.02.010 3D virtual modelling of physical experimental
equipment (elective subject, 1 credit; 2005)
E. Nõmmiste – FKEF.02.071 Hardware components (obligatory subject,
4 credits; 2004, 2005)
I. Ots, R. Saar – FKTF.04.013 Physics of elementary particles (elective
subject, 4 credits; 2005)
E. Realo – FKKF.03.001 Dosimetry in environment and radiation
protection I (obligatory/elective subject, 3 credits; 2004, 2005)
E. Realo – FKKF.03.073 Dosimetry in environment and radiation protection (obligatory/elective subject, 2 credits; 2005)
E. Realo – FKKF.03.075 Dosimetry in environment and radiation
protection II (elective subject, 4 credits; 2005)
200 • Biannual Report 2004/2005
I. Renge – FKMF.01.113 Fotoactive materials (elective subject, 2 credits;
2004, 2005)
K. Saal, T. Tätte – FKOK.01.046 Organic chemistry (practical works;
obligatory subject, 3 credits; 2004)
P. Saari – FKEF.04.007 Electricity and magnetism (obligatory subject,
4 credits; 2004, 2005)
P. Saari – FKEF.04.008 Fundamentals of signals and systems I (obligatory/elective subject, 2 credits; 2004, 2005)
P. Saari – FKEF.04.009 Fundamentals of signals and systems II
(obligatory/elective subject, 2 credits; 2004, 2005)
H. Siimon – FKMF.01.102 Structure of matter I (practical works; obligatory subject, 2 credits; 2004, 2005)
H. Siimon, T. Avarmaa, A. Floren, V. Kiisk, I. Kärkkänen, R. Rammula,
M. Pärs – FKMF.02.011 Structure of matter II (practical works,
obligatory/elective subject, 4 credits; 2005)
H. Siimon – FKMF.01.149 Materials physics. Mechanics and heat (practical
works I; obligatory subject, 4 credits; 2005)
H. Siimon, J. Kikas – FKMF.01.109 Physics of specific materials (obligatory
subject, 2 credits; 2005)
H. Siimon, J. Kikas – FKMF.01.069 Computer simulations (elective
subject, 2 credits; 2005)
H. Siimon, J. Kikas – FKMF.01.101 Structure of matter (seminars;
obligatory subject, 4 credits; 2005)
I. Sildos, V. Kiisk – FKMF.01.143 Spectroscopy II (elective subject,
1 credit; 2005)
12.2. Supevising of PhD theses
(postgraduates (doctoral level) of the University of Tartu)
J. Aarik
V. Hizhnyakov
R. Jaaniso
A. Kikas
N. Kristoffel
P. Kuusk U.
R. Rammula (2005)
V. Boltrushko (2005)
T. Jantson (2004), A. Floren (2005), A. Kärkkänen
(2005), I. Kärkkänen (2005)
K. Kooser (2004, 2005)
K. Rägo (2004)
Ivask (2004, 2005)
Pedagogical Activities • 201
T. Kärner
A. Lushchik
A. Lõhmus
K. Mauring
V. Nagirnyi
V. Palm
V. Peet
E. Realo
P. Saari
I. Sildos
A. Treshchalov
S. Zazubovich
S. Nakonechnyi (2004, 2005), V. Issakhanyan (2004,
2005)
A. Kotlov (2004), S. Nakonechnyi (2004, 2005),
V. Issakhanyan (2004, 2005)
K. Saal (2004, 2005), T. Tätte (2004, 2005), V. Reedo
(2004, 2005)
V. Krasnenko (2004, 2005)
A. Kotlov (2004)
M. Pärs (2005)
S. Shchemelev (2004, 2005)
E. Gershkevich (2004), T. Sisask (2004, 2005)
J. Pruulmann (2004, 2005)
V. Kiisk (2004, 2005), S. Lange (2005)
A. Lissovski (2004, 2005)
A. Krasnikov (2004, 2005)
12.3. Supervising of MSc theses
(postgraduates (master level) of the University of Tartu
J. Aarik
T. Avarmaa
V. Fedoseyev
A. Freiberg
V. Hizhnyakov
R. Jaaniso
M. Kiisk
I. Kink
A. Kotlov
A. Lushchik
A. Lõhmus
R. Lõhmus
K. Mauring
R. Rammula (2004)
K. Õige (2004)
U. Repinski (2004, 2005)
D. Troskov (2004)
V. Boltrushko (2004)
A. Floren (2004), A. Kärkkänen (2004), I. Kärkkänen
(2004), M. Kodu (2005)
L. Aarik (2004, 2005), K. Isakar (2004, 2005)
J. Shulga (2005)
R. Sarakvasha (2005)
S. Galayev (2005)
M. Lobjakas (2004, 2005)
U. Vesi (2004, 2005), M. Lobjakas (2004, 2005),
S. Leinberg (2005), S. Vlassov (2005), M. Timusk
(2005)
S. Miller (2005)
202 • Biannual Report 2004/2005
V. Nagirnyi
A. Niilisk
E. Nõmmiste
V. Palm
V. Peet
E. Realo
K. Rebane
V. Reedo
K. Reivelt
A. Rosental
K. Saal
P. Saari
I. Sildos
A. Suisalu
A. Sherman
A. Tarre
T. Tätte
S. Zazubovich
E. Vasil’chenko
R. Sarakvasha (2005)
R. Pärna (2005)
T. Hein (2004, 2005)
M. Pärs (2004)
S. Burak (2004, 2005)
A. Uljas (2004, 2005), L. Aarik (2004, 2005), K. Isakar
(2004, 2005)
M. Pärs (2004)
M. Järvekülg (2005)
H. Valtna (2004, 2005)
R. Pärn (2005)
M. Plaado (2005)
H. Valtna (2004, 2005), G. Savustyan (2005)
S. Lange (2004), M. Pärs (2004), A. Lukner (2005)
M. Kleemann (2004, 2005), U. Visk (2005)
D. Bobkov (2004, 2005)
R. Pärn (2005)
M. Paalo (2005)
A. Makhov (2005)
S. Galayev (2005)
13. AWARDS
2004
The Estonian Science Prize for long and productive research and
development – Ch. Lushchik
The Estonian Science Prize in exact sciences – N. Kristoffel, Mechanism of
MgB2 superconductivity
The Prize of the Estonian Ministry of Education and Research for the
students’ investigations published in 2004 – postgraduate students
A. Krasnikov, H. Valtna
The Science Prize of the Estonian Science Foundation for the postgraduate
students (doctoral level) – V. Issakhanyan, V. Kiisk, A. Kotlov,
A. Krasnikov
The Students’ Scholarship of the Institute of Physics, UT – V. Issakhanyan,
M. Kleeman, V. Krasnenko, S. Vlassov
2005
The Estonian Science Prize in technical sciences – A. Lõhmus, R. Lõhmus,
Development of micro- and nanotechnological research methods for
elaboration of industrial materials
The Annual Prize of the Estonian Physical Society – J. Aarik, Advancement of
atomic layer deposition method and investigation of this films prepared by
this technique
The Prize of the Estonian Ministry of Education and Research for the
students’ investigations published in 2005 – postgraduate student
A. Krasnikov
The Students’ Prize of the Estonian Academy of Sciences – M. Moppel,
Development of confocal microscope for Raman and luminescence
measurements
204 • Biannual Report 2004/2005
The Best Poster Award of TNT2005 “Trends in Nanotechnology” (Ovideo)
– M. Järvekülg
The Best Poster Award of International Conference “Atomic and Molecular
Pulsed Lasers” (Tomsk) – A. Lissovski
The Students’ Scholarship of the Institute of Physics, UT – M. Järvekülg,
M. Paalo, U. Visk, H. Valtna, S. Lange, R. Rammula.
14. ACKNOWLEDGEMENTS
Institute of Physics and its laboratories would like to thank our colleagues
from the following universities, institutions and organizations for fruitful
scientific co-operation and/or financial support in 2004–2005:
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Australian Nuclear Science and Technology Organization (ANSTO),
Materials Division, Dr. D.R.G. Mitchell
Chemnitz University of Technology, Prof. M. Schreiber
CNR-NATO Outreach Fellowship
Crafoord Foundation
Cornell University, Prof. A.J. Sievers
Danish University of Technology, Prof. J. Bohr
Deutsche Forschungsgemeinschaft
Estla Ltd., J. Berik
Estonian Science Foundation
European Commission
Hasselblad Foundation
Lund University, MAX-Lab, Prof. N. Mårtensson
Lund University, Department of Atomic Spectroscopy, Prof. I. Martinson
NordForsk
Trygger Foundation
University of Hamburg, Prof. G. Zimmerer, Prof. W. Wurth
University of Milan-Bicocca, Prof. G. Benedek
University of Oulu, Prof. S. Aksela
University of Uppsala, Ångström Laboratory, Dr. Jun Lu, Dr.
M. Ottoson, Prof. A. Harsta
University of Valladolid, Prof. S. Duena