Download Scholarly Interest Report

F. Barry Dunning
Professor
Sam and Helen Worden Professor of Physics
e-mail:[email protected]


B.Sc. (Special) First Class Honors, (1966) University
College London, London, England
Ph.D., (1969) University College London, London,
England
Primary Department
Department of Physics and Astronomy
Department Affiliations
 Department of Physics and Astronomy
Research Areas
Experimental Atomic, Molecular, and Optical Physics, Nonlinear Dynamics, Chemical Physics.
Research Statement
My research focuses on atoms in which one electron is excited to a state of very large principal quantum number n, termed
Rydberg atoms. Such atoms possess properties quite unlike those normally associated with atoms in ground or low-lying
excited states. For example, because the size of an atom scales as n2, they are physically very large. An atom with n~400
has a diameter approaching 20 m. Their classical electron orbital periods are also very long, ~10 ns at n~400, and this we
exploit to control and manipulate their electronic wave functions using pulsed electric fields whose characteristic times
(duration, rise/fall times) are less than this period. Application of such pulses leads to the formation of wave packets that
comprise a coherent superposition of adjacent Rydberg states. These wave packets display novel dynamical behavior that can
mimic the classical motion of an excited electron, thereby providing a bridge between quantum and classical physics. Our
studies show that, with careful choice of the amplitude and width of the pulses (or application of several pulses), it is possible
to control and manipulate atomic wavefunctions with remarkable precision. The goal is to use carefully-tailored sequences
of pulses to engineer atomic wavefunctions and produce “designer” atoms to study classical-quantum correspondence, to use
periodic trains of pulses to create non-dispersive wave packets and to probe non-linear dynamics and classical/quantum
chaos, to study atom/field interactions in the ultra-fast ultra-intense regime, to explore information storage/retrieval in atoms,
and to study the behavior of strongly-coupled Rydberg/Rydberg systems. Initial work centered on potassium Rydberg atoms
contained in a tightly-collimated atomic beam but has now been extended to include strontium Rydberg atoms contained in
both an atomic beam and in an ultra-cold atomic gas or Bose-Einstein condensate (BEC).
The starting point for many of our studies is the production of strongly-polarized quasi-one-dimensional (quasi-1D) high-n
Rydberg atoms by photo-exciting extreme red-shifted Stark states in the presence of a weak dc field. Protocols have been
developed using pulsed electric fields to characterize such states and monitor their time evolution. Techniques have also
been devised to convert such states into quasi-two-dimensional (quasi-2D) “circular” states in which the electron orbits in a
plane, and probe their evolution. The opportunities afforded by the creation of quasi-1D and -2D atoms are being explored.
These include the use of periodic drive fields to create localized non-dispersive wave packets that mimic the behavior of a
classical electron and to transport these wave packets to states of higher n. Measurements with strontium Rydberg atoms
show that, even at high n, the regime where dipole blockade becomes important can be accessed opening up new
opportunities to study strongly-coupled Rydberg atom pairs and their possible manipulation to form long-lived “molecular”
species through periodic driving. The production of long-lived “planetary atom” states in strontium that contain two excited
electrons is also being examined. Studies of the control of the interactions between atoms in a strontium BEC by dressing
the ground-state atoms with an admixture of a higher-lying Rydberg state using lasers have been initiated with the long-range
goal of realizing soliton formation in three dimensions and creation of a supersolid. Ultralong-range Rydberg molecules in
which the scattering of the Rydberg electron from a neighboring ground state atom binds the two together in a novel
chemical bond is being explored. Initial spectroscopic studies have focused on dimer Rydberg molecules. Measurments are
being extended to trimer, tetramer . . . molecular states in which two, three . . . ground-state atoms are bound to the Rydberg
atom to examine their lifetimes and the details of their energy level structure. It is planned to use such species to probe nonlocal pair correlations in a quantum gas.
Because the Rydberg electron is typically far from its associated core ion it will, in collisions with neutral targets, behave as
an independent particle allowing a Rydberg atom to be viewed as an ultra-low-energy electron trap. Potassium Rydberg
atoms are therefore being used to examine electron attachment to molecules. The creation of novel negative ion species in
such collisions is observed including the formation of negative ions in which the electron is weakly bound by the electric
dipole moment of the parent molecule. The creation of heavy-Rydberg ion-pair states comprising a positive-negative ion
pair that orbit at large radius weakly bound by their mutual electrostatic attraction is also seen. The physical and chemical
properties of such species are being examined using a newly-commissioned apparatus. Measurements are being extended to
elucidate the role of dipole binding in creating heavy-Rydberg ion pair states and in inducing strong Rydberg atom
scattering. The reactions of ion pair states in collisions with neutral targets are also being examined.
Each of the above experimental programs makes use of advanced experimental techniques including ultrahigh vacuum
technology, state-of-the-art dye and diode laser systems, high-speed analog and digital electronics, and computer-based data
acquisition and control systems. The work relies heavily on the efforts of several graduate students:
Michael Kelley
Xinyue Zhang
Sitti Buathong
Roger Ding
Gavin Fields
Research Topics
Schemes for the production of quasi-1D high-n Rydberg atoms in the blockade regime where the excitation of one atom
inhibits the subsequent excitation of its neighbors are being explored as this allows the controlled production of Rydberg
atoms with well-defined initial separations. At n~300, creation of a quasi-1D atom, for an effective laser linewidth of ~5
MHz, suppress excitation of a second similar atom within a radius of ~100 m extending strong many-body interactions
well into the mesoscopic regime. Measurements using two- and three-photon excitation of strontium atoms in a beam show
that it is possible to achieve the required neutral atom densities in an atomic beam to see efficient blockade. Access to the
dipole blockade regime enables detailed studies of the interactions between strongly-coupled Rydberg atoms and their
dependence on the coupling strength, which can be varied by changing their separation or by changing n using the techniques
we have already developed to manipulate the atomic state. Questions of interest focus on the dynamics of energy
interchange and their dependence on the degree of coupling. Excitation to Rydberg states whose size is comparable to the
interatomic spacing will lead to the formation of a transient Rydberg “molecule” whose stability against autoionization is
governed by electron-electron scattering. Of particular interest are long-lived configurations where, due to their correlated
motions, the electrons remain far apart suppressing autoionization. Such states might also, by locking the electron motion to
periodic driving with an electric field, lead to formation of a correlated phase-locked Rydberg pair wave packet.
In other experiments strong tunable long-range interactions are being created in cold atom samples and BECs by dressing
ground state strontium atoms contained in an optical dipole trap with an admixture of an excited Rydberg level using laser
radiation tuned near resonance with the transition to the Rydberg state. Strontium possesses narrow intercombination lines
which can be used to obtain significantly longer sample lifetimes and decoherence times as compared to the use of alkali
atoms. These ongoing experiments will advance our understanding of quantum materials and emergent phenomena and lead
to new technological advances. Initial measurements, however, have revealed that even
weak Rydberg dressing can lead to surprisingly large ground state atom loss rates
from the trap. The processes responsible continue to be examined but are
attributed to the excitation of Rydberg atoms which can result in direct trap loss
through recoil and in the population of very-long-lived metastable
states. Measurements of the time dependence of the trap loss suggest a
mechanism in which the creation of a small number of “seed” Rydberg atoms
triggers “avalanche-like” growth in the numbers of Rydberg atoms excited. This
work shows that, if effects due to Rydberg dressing are to be observed, small
samples and/or short time scales may be essential. To this end, the use of AutlerTownes spectroscopy has been exploited to study the effects of interactions
induced by Rydberg dressing on timescales of a few microseconds. The
mechanisms responsible for trap loss are being further explored by directly
monitoring the growth of the Rydberg atom population and its distribution in n and
l.
Spectroscopic measurements of trap loss also revealed the production of verylong-range weakly-bound Rydberg molecules in which scattering of the excited
Rydberg atom from a neighboring ground state atom can bind the two atoms
together. Detailed studies of such molecules are underway as they represent a
new type of chemical bond and can display surprising features such as the
presence of large permanent electric dipole moments, even in the case of a
homonuclear molecule. Measurements reveal the production of Rydberg
molecules in both ground and excited vibrational states whose energies are in
excellent agreement with those predicted theoretically. The data also show the
presence of features that result from the creation of trimer (tetramer) states that
comprise a parent Rydberg atom and two (three) bound atoms and whose
energies are given approximately by the separate binding energies of the
atoms. Measurements on these novel species are continuing to compare their
properties (lifetimes, electric field ionization characteristics, etc.) to those of the
parent Rydberg atoms. Of particular interest is the degree to which the bound
ground state atoms behave as independent particles and the possible use of
ultralong-range Rydberg molecules as a tool to probe non-local pair correlations in
a quantum gas in the previously inaccessible length scale of ~20-200 nm. In
addition, the behavior of Rydberg molecules in a dense quantum gas, i.e., BEC, is
being examined to search for novel many-body effects and to characterize the
processes that lead to their destruction in such an environment.
Collisions between high-n Rydberg atoms and molecular targets are being used to examine electron attachment to
molecules. The creation of novel negative ion species is observed including the formation of ions in which the electron is
weakly bound by the electric dipole moment of the parent molecule. Such ions display many of the characteristics associated
with Rydberg atoms which is, perhaps, not unexpected as they both contain a weakly-bound electron in a diffuse orbital.
Rydberg atom collisions can also lead to creation of so-called heavy-Rydberg ion-pair states comprising a positive-negative
ion pair that orbit at large radius weakly bound by their mutual Coulomb attraction. The lifetimes and decay modes of such
species are being examined. Ion-pair states involving molecular negative ions can decay through mutual charge transfer or
the conversion of internal energy in the negative ion into translational energy of the ion pair. Those states involving atomic
negative ions have very long lifetimes, allowing studies of their chemical and collisional properties. Measurements are being
extended to elucidate the role of dipole-binding in creating heavy-Rydberg ion pair states and in inducing strong Rydberg
atom scattering. The reactions of ion pair states in collisions with neutral targets are being explored.
Each of the above experimental programs makes use of advanced experimental techniques including ultrahigh vacuum
technology, state-of-the-art dye, diode and fiber laser systems, high-speed analog and digital electronics, and computer-based
data acquisition and control systems. The work relies heavily on the efforts of several graduate students:
Michael Kelley
Xinyue Zhang
Sitti Buathong
Roger Ding
Gavin Fields
Teaching Areas
Freshman physics, Sophomore physics, Graduate Student advising
Selected Publications
Refereed articles
Aman, J. A., B. J. DeSalvo, F. B. Dunning, T. C. Killian, S. Yoshida, and J. Burgdörfer "Trap
losses induced by near-resonant Rydberg dressing of cold atomic gases,” ." Physical Review A,
93 (2016) : 043425.
Buathong, S, M. Kelley, and F. B. Dunning "Probing dissociative electron attachment through
heavy-Rydberg ion-pair production in Rydberg atom collisions." Journal of Chemical Physics,
145 (2016) : 134309.
Camargo, F.,J. D. Whalen, R. Ding, H. R. Sadeghpour, S. Yoshida, J. Burgdörfer, F. B.
Dunning, and T. C. Killian "Lifetimes of ultra-long-range strontium Rydberg
molecules." Phycial Review A, 93 (2016) : 022702.
DeSalvo, B. J., J. A. Aman, C. Gaul, T. Pohl, S. Yoshida, J. Burgdörfer, K. R. A. Hazzard, F. B.
Dunning, and T. C. Killian "Rydberg-blockade effects in Autler-Townes spectra of ultracold
strontium." Physical Review A, 93 (2016) : 022709.
Dunning, F. B., T. C. Killian, S. Yoshida, and J. Burgdörfer "Recent advances in Rydberg
physics using alkaline-earth atoms." Journal of Physics B, 49 (2016) : 112003.
Gaul, C., B. J. DeSalvo, J. A. Aman, F. B. Dunning, T. C. Killian, and Thomas Pohl "Resonant
Rydberg-dressing of alkaline-earth atoms via electromagnetically induced
transparency." Physical Review Letters, 116: 243001.
Yoshida, S., J. Burgdörfer, X. Zhang, and F. B. Dunning "Rydberg blockade in a hot atomic
beam." Physical Review A (2016) Submitted
B. J. DeSalvo, J. A. Aman, F. B Dunning, T. C. Killian, H. R. Sadeghpour, S. Yoshida, and J.
Burgdörfer "Ultralong-range Rydberg molecules in a divalent atomic system." Physical Review
A, 92 (2015) : 031403(R).
M. Kelley, S. Buathong, and F. B. Dunning "Use of heavy-Rydberg ion-pair states to probe
dissociative electron attachment." Journal of Physics: Conference Series, 635 (2015) :
012024.
S. Buathong, M. Kelley, C. H. Wang, and F. B. Dunning "Probing dissociative electron
attachment through formation of heavy-Rydberg ion pair states in Rydberg atom
collisions." Chemical Physics Letters, 618 (2015) : 153.
X. Zhang, F. B. Dunning, S. Yoshida, and J. Burgdörfer "Rydberg blockade effects at n~300 in
strontium." Physical Review A, 92 (2015) : 051402(R).
C. H. Wang, M. Kelley, S. Buathong, and F. B. Dunning "Dynamics of heavy-Rydberg ion-pair
formation in K(14p,20p)-SF6, CCl4 collisions." Journal of Chemical Physics, 140 (2014) :
234306.
M. Hiller, S. Yoshida, J. Burgdörfer, S. Ye, X. Zhang, and F. B. Dunning "Characterizing high-n,
quasi-one-dimensional strontium Rydberg atoms." Physical Review A, 89 (2014) : 023426.
S. Buathong, M. Kelley, C. H. Wang, and F. B. Dunning "Probing dissociative electron
attachment through formation of heavy-Rydberg ion pair states in Rydberg atom
collisions." Chemical Physics LettersIn Press
S. Ye, X. Zhang, F. B. Dunning, S. Yoshida, M. Hiller, and J. Burgdörfer "Efficient three-photon
excitation of quasi-one-dimensional strontium Rydberg atoms with n~300." Physical Review A,
90 (2014) : 013401.
Korana Burke, Kevin A. Mitchell, Shuzhen Ye, and F. Barry Dunning "Chaotic ionization of a
stationary electron state via a phase space turnstile." Phys. Rev. A, 88 (2013) : 01308.
P. McQuillen, X. Zhang, T. Strickler, F. B. Dunning, and T. C. Killian "Imaging the evolution of
an ultracold strontium Rydberg gas." Phys. Rev. A, 87 (2013) : 013407.
S. Ye, X. Zhang, T.C. Killian, F.B.Dunning, M. Hiller, S. Yoshida, S. Nagele, and J. Burgdorfer
"Production of very-high-n strontium Rydberg atoms." Phys. Rev. A, 88 (2013) : 043430.
Y. Pu and F. B. Dunning "Ionization of Rydberg atoms at patterned electrode arrays." Phys.
Rev. A, 88 (2013) : 012901.
B. Wyker, S. Ye, F. B. Dunning, S. Yoshida, C. O. Reinhold, and J. Burgdörfer "Creating and
transporting Trojan wave packets." Phys. Rev. Lett., 108 (2012) : 043001.
S. Yoshida, C. O. Reinhold, J. Burgdörfer, B. Wyker, S. Ye, and F. B. Dunning "Analysis of
circular wave packets generated by pulsed electric fields." Nucl. Inst. Meth. Phys. Res. B, 279
(2012) : 4-7.
S. Yoshida, C. O. Reinhold, J. Burgdörfer, S. Ye, and F. B. Dunning "Photoexcitation of n~305
Rydberg atoms in the presence of an rf drive field." Phys. Rev. A, 86 (2012) : 043415.
B. Wyker, S. Ye, F. B. Dunning, S. Yoshida, C. O. Reinhold and J. Burgdörfer "Probing the
spatial distribution of high angular momentum Rydberg wave packets." Phys. Rev. A, 84
(2011) : 043412.
B. Wyker, S. Ye, T. J. McKinney, F. B. Dunning, C. O. Reinhold, S. Yoshida, and J. Burgdörfer
"Decoherence of high-l Rydberg wave packets." J. Phys. B: At. Mol. Opt. Phys., 44 (2011) :
184002.
C. O. Reinhold. S. Yoshida, and F, B, Dunning "Electric-field-induced dissociation of heavy
Rydberg ion-pair states." J. Chem. Phys., 134 (2011) : 174305.
C. O. Reinhold. S. Yoshida, and F, B, Dunning "Electric-field-induced dissociation of heavy
Rydberg ion-pair states." J. Chem. Phys., 134 (2011) : 174305.
D. D. Neufeld, Y. Pu, and F. B. Dunning "Probing stray surface electric patch fields using
Rydberg atoms." Nucl. Instr. and Meth. B, 269 (2011) : 1288.
K. Burke, K. A. Mitchell, B. Wyker, S. Ye, and F. B. Dunning "Demonstration of turnstiles as a
chaotic ionization mechanism in Rydberg atoms." Phys. Rev. Lett., 107 (2011) : 113002.
F. B. Dunning, C. O. Reinhold, S. Yoshida, and J. Burgdörfer "Steering quantum states
towards classical Bohr-like orbits." Am. J. Phys., 78 (2010) : 796.
M. Cannon, C. H. Wang, F. B. Dunning, and C. O. Reinhold "Lifetimes of heavy-Rydberg ionpair states formed through Rydberg electron transfer." , 133 (2010) : 064301.
S. Yoshida, C. O. Reinhold, J. Burgdörfer, B. Wyker, and F. B. Dunning "Encoding and
decoding information in high-n circular wave packets." Phys. Rev. A, 81 (2010) : 063428.
Y. Pu, D. D. Neufeld, and F. B. Dunning "Ionization of Rydberg atoms at metallic
surfaces." Phys. Rev. A, 81 (2010) : 042904.
C. O. Reinhold, S. Yoshida, J. Burgdörfer, B. Wyker, J. J. Mestayer, and F. B. Dunning "Large
scale quantum coherence of nearly circular wave packets." J. Phys. B:At. Mol. Opt. Phys., 42,
091003 (2009)
F. B. Dunning, J. J. Mestayer, C. O. Reinhold, S. Yoshida, and J. Burgdörfer "Engineering
atomic Rydberg states with pulsed electric fields." J. Phys. B: At. Mol. Opt. Phys., 42, 022001
(2009)
J. J. Mestayer, B. Wyker, F. B. Dunning, S. Yoshida, C. O. Reinhold, and J. Burgdörfer
"Creation of non-dispersive Bohr-like wavepackets." Phys. Rev. A, 79, 033417 (2009)
M. Cannon and F. B. Dunning "Formation of heavy Rydberg ion-pair states in collisions of
K(np) Rydberg atoms." J. Chem. Phys., 130, 044304 (2009)
M. Cannon, C. H. Wang, Y. Liu, F. B. Dunning, and J. D. Steill "Temperature dependence of
reactions involving electron transfer in K(np)/C2Cl4 collisions." J. Chem. Phys., 130, 244311
(2009)
M. Cannon, C. H. Wang, and F. B. Dunning "Direct observation of K+..Cl- heavy Rydberg ionpair states formed in K(np)/CCl4 collisions." Chem. Phys. Lett., 479, 30 (2009)
S. Yoshida, C. O. Reinhold, J. Burgdörfer, and F. B. Dunning "Comment on "Nondispersing
Bohr wave packets"." Phys. Rev. Lett., 103, 149301 (2009)
C. O. Reinhold, S. Yoshida, J. Burgdorfer, J. J. Mestayer, B. Wyker, J. C. Lancaster and F. B.
Dunning "Tailoring very-high-n circular wave packets" Phys. Rev. A 78, 063413 (2008)
D. D. Neufeld, H. R. Dunham, S. Wethekam, J. C. Lancaster, and F. B. Dunning "Ionization of
xenon Rydberg atoms at Au(111) surfaces: Effect of stray fields" Phys. Rev. B 78, 115423
(2008)
D. D. Neufeld, H. R. Dunham, S. Wethekam, J. C. Lancaster, and F. B. Dunning "Ionization of
xenon Rydberg atoms at oxidized Si(100) surfaces" Surf. Sci. 602, 1306 (2008)
J. J. Mestayer, B. Wyker, F. B. Dunning, C. O. Reinhold, S. Yoshida and J. Burgdorfer
"Generation of quasi-classical Bohr-like wavepackets using HCPs" Phys. Rev. A 78, 045401
(2008)
J. J. Mestayer, B. Wyker, J. C. Lancaster, F. B. Dunning, C. O. Reinhold, S. Yoshida and J.
Burgdorfer "Realization of localized Bohr-like wave packets" Phys. Rev. Lett. 100, 243004
(2008)
M. Cannon, Y. Liu, L. Suess, and F. B. Dunning "Dipole-bound CH3CN- ions: Temperature
dependence of ion production rates and lifetimes" J. Chem. Phys. 128, 244307 (2008)
M. Cannon, Y. Liu, and F. B. Dunning "Lifetime of K+-SF6- heavy Rydberg states formed by
electron transfer in K(np)-SF6 collisions" Chem. Phys. Lett. 458, 35 (2008)
S. Yoshida, C. O. Reinhold, J. Burgdorfer, W. Zhao, J. J. Mestayer, and J. C. Lancaster
"Extracting irreversible de-phasing rates from electric dipole echoes in Rydberg Stark wave
packets" Phys. Rev A 78, 063414 (2008)
S. Yoshida, C. O. Reinhold, J. Burgdorfer. J. J. Mestayer, J. C. Lancaster and F. B. Dunning
"Transferring Rydberg wave packets between islands across the chaotic sea" Phys. Rev. A 77,
013411 (2008)
Refereed conference papers
B. J. DeSalvo, J. A. Aman, F. B. Dunning, T. C. Killian, S. Yoshida, and J. Burgdörfer "Trap
losses due to near-resonant Rydberg dressing of cold atomic gases." Journal of Physics:
Conference Series, 635 (2015) : 092024.
B. J. DeSalvo, J. Aman, F. B. Dunning, T. C. Killian, H. R. Sadeghpour, S. Yoshida, and J.
Burgdörfer "Production of ultra-long-range Rydberg molecules in a divalent atomic
system." Journal of Physics: Conference Series, 635 (2015) : 092023.
M. Kelley, S. Buathong, and F. B. Dunning "Use of heavy-Rydberg ion-pair states to probe
dissociative electron attachment." Journal of Physics: Conference Series, 635 (2015) :
072002.
X. Zhang, F. B. Dunning, S. Yoshida, and J. Burgdörfer "Exploiting Rydberg blockade to probe
strongly-coupled Rydberg atom pairs." Journal of Physics: Conference Series, 635 (2015) :
092022.
M. Hiller, S. Yoshida, J. Burgdörfer, S. Ye, X. Zhang, and F. B. Dunning "Creation of quasione-dimensional high-n strontium Rydberg atoms." Journal of Physics: Conference Series, 488
(2014) : 032002.
S. Ye, X. Zhang, T. C. Killian, F. B. Dunning, M. Hiller, S. Yoshida, and J. Burgdörfer
"Production of high-n strontium Rydberg atoms." Journal of Physics: Conference Series, 488
(2014) : 022003.
B. Wyker, S. Ye, F. B. Dunning, S. Yoshida, C. O. Reinhold, and J. Burgdörfer "Probing and
manipulating high-n near-circular Rydberg wave packets." Journal of Physics: Conf. Series,
388 (2012) : 032001.
B. Wyker, S. Ye, F. B. Dunning, S. Yoshida, C. O. Reinhold, and J. Burgdörfer "Transporting
near-circular Bohr-like wave packets using chirped sine waves." Journal of Physics: Conf
Series, 388 (2012) : 032001.
C. O. Reinhold, S. Yoshida, and F. B. Dunning "Field-induced dissociation of Rydberg ion-pair
states." Journal of Physics: Conf. Series, 388 (2012) : 022064.
S. Yoshida, C. O. Reinhold, J. Burgdörfer, B. Wyker, S. Ye, and F. B. Dunning "Decoherence of
high-n, high-l Rydberg wave packets by electrical noise and collisions." Journal of Physics:
Conf. Series, 388 (2012) : 032003.
Presentations
Conference abstracts
Group leader. "Blockade involving high-n, n~300, strontium Rydberg atoms." Annual meeting
of the Division of Atomic, Molecular & Optical Physics/ American Physical Society, Providence,
Rhode Island. (May 2016) With Shuhei Yoshida, Joachim Burgdörfer, Xinyue Zhang
Group leader. "Controlling autoionization in strontium two-electron-excited states." Annual
meeting of the Division of Atomic, Molecular & Optical Physics/ American Physical Society,
Providence, Rhode Island. (May 2016) With Robert Fields, Xinyue Zhang, Shuhei Yoshida, and
Joachim Burgdörfer
Co-group leader. "Lifetimes of ultra-long-range strontium Rydberg molecules." Annual
meeting of the Division of Atomic, Molecular & Optical Physics/ American Physical Society,
Providence, Rhode Island. (May 2016) With F. Camargo, J. D. Whalen, R. Ding, H. R.
Sadeghpour, S. Yoshida, J. Burgdörfer, and T. C. Killian
Co-group leader. "Molecular spectra in an ultracold strontium Rydberg gas." Annual meeting
of the Division of Atomic, Molecular & Optical Physics/ American Physical Society, Providence,
Rhode Island. (May 2016) With Joseph D. Whalen, Francisco Camargo, Roger Ding, Germano
Woehl, Jr., Thomas C. Killian
Co-group leader. "Progress towards isotope-dependent trapping of strontium." Annual
meeting of the Division of Atomic, Molecular & Optical Physics/ American Physical Society,
Providence, Rhode Island. (May 2016) With Roger Ding, Francisco Camargo, Joseph D.
Whalen, Germano Woehl, Jr, Thomas C. Killian
Group leader. "Studying dissociative electron attachment through formation of heavyRydberg ion-pair states." Annual meeting of the Division of Atomic, Molecular & Optical
Physics/ American Physical Society, Providence, Rhode Island. (May, 2016) With Michael
Kelley and Sitti Buathong
Invited Papers
"Production of heavy-Rydberg ion-pair states through Rydberg electron transfer." ITAMP
Heavy Rydberg Physics Workshop, Harvard-Smithsonian Center for Astrophysics, Cambridge,
MA. (May 2012)
"Atomic engineering: Creation of localized very-high-n "Bohr-like" wavepackets." Engineering
Rydberg Interactions in Atoms, Molecules and Plasmas: a Collaborative Workshop, Institute
for Theoretical Atomic, Molecular and Optical Physics, Harvard. (September, 2009)
"Generation of localized "Bohr-like" wavepackets in near-circular orbit about the nucleus."
Division of Atomic, Molecular, and Optical Physics of the American Physical Society, University
of Virginia, Charlottesville, Virginia. (May, 2009)
"Designer atoms: Engineering Rydberg atoms using pulsed electric fields." Workshop on
Rydberg Excited atoms/Lundbeck Foundation, Sandbjerg, Denmark. (May 2008)
Invited Talks
speaker. "Strontium Rydberg atoms: A new tool for probing interacting systems." University
of Durham, Durham, England. (June 2015)
Research director. "Use of heavy-Rydberg ion-pair states to probe dissociative electron
attachment." International Conference on Photonic, Electronic and Atomic Collisions, Toledo,
Spain. (July 2015) With M. Kelley, and S. Buathong
Presenter. "Engineering high-n wavepackets." Winter Graduate School on Atomic, Molecular
and Optical Physics, Inst. for Theor. At. Mol. and Opt. Phys., Biosphere 2 Conference Center,
Tucson, Arizona. (Jan 4-12 2014) With B. Wyker, J. J.Mestayer, S. Ye, X. Zhang
Presenter. "Engineering near-circular high-n wavepackets." Winter Graduate School on
Atomic, Molecular and Optical Physics, Inst. for Theor. At. Mol. and Opt. Phys., Biosphere 2
Conference Center, Tucson, Arizona. (Jan 4-12, 2014) With B. Wyker, J. J. Mestayer, S. Ye.,
X. Zhang
Presenter. "Experiments with strontium Rydberg atoms." Winter Graduate School on Atomic,
Molecular and Optical Physics, Inst. for Theor. At. Mol. and Opt. Phys., Biosphere 2
Conference Center, Tucson, Arizona. (Jan 4-12 2014) With S. Ye, X. Zhang, J. Aman, F.
Camargo, B. DeSalvo, R. Ding, P. McQuillen, T. Strickler, T. C. Killian
Presenter. "Experiments with strontium Rydberg atoms." Second International Workshop on
Ultracold Rydberg Physics/Univ. de Sao Paulo, Brazil, Recife, Brazil. (Oct 5-8, 2014)
"Probing stray electric fields at surfaces with Rydberg atoms." American Physical Society,
Division of Atomic, Molecular & Optical Physics, Quebec City, Canada. (June 2013)
"Probing stray electric fields at surfaces with Rydberg atoms." Conference on Inelastic IonSurface Collisions - IISC18, Gatlinburg, TN. (September 2010) With D. D. Neufeld
Studies with near-circular high-n wavepackets -Cold Rydberg Gases and Ultracold Plasmas MPIPKS-ITAMP Tandem Workshop, Dresden
Other
"Extracting irreversible dephasing rates from the echoes of Rydberg Stark wavepackets."
Division of Atomic, Molecular, and Optical Physics of the American Physical Society, State
College, Pennsylvania. (May 27-31, 2008) With J. J. Mestayer, B. Wyker, C. O. Reinhold, S.
Yoshida and J. Burgdörfer
"Formation of heavy Rydberg K+-SF6- ion-pair states in K(np)-SF6 collisions." Division of
Atomic, Molecular, and Optical Physics of the American Physical Society, State College,
Pennsylvania. (May 27-31, 2008) With M. Cannon, Y. Liu
"Ionization of Xe(nf) Rydberg atoms at surfaces: Effect of stray fields." Division of Atomic,
Molecular, and Optical Physics of the American Physical Society, State College, Pennsylvania.
(May 27-31, 2008) With D. D. Neufeld, H. R. Dunham, S. Wethekam, J. C. Lancaster
"Realization of Bohr-like circular wavepackets." Division of Atomic, Molecular, and Optical
Physics of the American Physical Society, State College, Pennsylvania. (May 27-31, 2008)
With J. J. Mestayer, B. Wyker, C. O. Reinhold, S. Yoshida and J. Burgdörfer
"Transferring Rydberg wavepackets between islands across the chaotic sea." Division of
Atomic, Molecular, and Optical Physics of the American Physical Society, State College,
Pennsylvania. (May 27-31, 2008) With S. Yoshida, C. O. Reinhold, J. Burgdörfer. J. J.
Mestayer, B. Wyker
Posters
Group leader. "Creation, control, and detection of Rydberg excitations in ultracold strontium."
American Physical Society, Division of Atomic, Molecular and Optical Physcis, Columbus, Ohio.
(June 2015) With Joseph Whalen, Roger Ding, Francisco Camargo, German Woehl, Jr, Thomas
Killian
Group leader. "Heavy-Rydberg ion-pair formation in Rydberg atom collisions: probing
dissociative electron attachment." American Physical Society, Division of Atomic, Molecular
and Optical Physics, Columbus, Ohio. (June 2015) With Michael Kelley, Sitti Buathong
Group leader. "New approaches for producing quantum degenerate gases of strontium."
American Physical Society, Division of Atomic, Molecular and Optical Physics, Columbus, Ohio.
(June 2015) With Roger Ding, Germano Woehl, Jr, Francisco Camargo, Joseph Whalen,
Thomas Killian
Group leader. "Observation of Rydberg blockade effects at very high n, n~300 using
strontium n1F3 states." American Physical Society, Division of Atomic, Molecular and Optical
Physics, Columbus, Ohio. (June 2015) With Xinyue Zhang, Shuhei Yoshida, Joachim
Burgdörfer
Group leader. "Producing quantum degenerate gases of strontium." American Physical
Society, Division of Atomic, Molecular and Optical Physics, Columbus, Ohio. (June 2015) With
Francisco Camargo, Roger Ding, Joseph Whalen, Germano Woehl, Thomas Killian
Group leader. "Rydberg blockade effects on Autler-Townes spectra in a dense gas of 84Sr."
American Physical Society, Division of Atomic, Molecular and Optical Physics, Columbus, Ohio.
(June 2015) With B. J. DeSalvo, J. A. Aman, T. C. Killian
Group leader. "Strongly-coupled high-n Rydberg atom pairs." American Physical Society,
Division of Atomic, Molecular and Optical Physics, Columbus, Ohio. (June 2015) With Shuhei
Yoshida, Joachim Burgdörfer, Xinyue Zhang
Group leader. "Trap losses induced by Rydberg dressing of cold atomic gases." American
Physical Society, Division of Atomic, Molecular and Optical Physics, Columbus, Ohio. (June
2015) With J. A. Aman, B. J. DeSalvo, T. C. Killian
Presenter. "An experimental apparatus for studying Rydberg-Rydberg interactions in quantum
degenerate gases of strontium." Division of Atomic, Molecular, and Optical Physics, American
Physical Society, Madison, Wisconsin. (Jun 2-6, 2014) With Francisco Camargo, Roger Ding,
James Aman, Xinyue Zhang, Joseph Whalen, Robert Fields, Thomas Killian
Presenter. "Characterizing high-n quasi-one-dimensional strontium Rydberg atoms." Division
of Atomic, Molecular, and Optical Physics, American Physical Society, Madison, Wisconsin. (Jun
2-6, 2014) With Moritz Hiller, Shuhei Yoshida, Joachim Burgdörfer, Shuzhen Ye, Xinyue Zhang
Presenter. "Efficient three-photon excitation of quasi-1D n~300 strontium Rydberg atoms."
Division of Atomic, Molecular, and Optical Physics, American Physical Society, Madison,
Wisconsin. (Jun 2-6, 2014) With Xinyue Zhang, Shuzhen Ye, Shuhei Yoshida, Moritz Hiller,
Joachim Burgdörfer
Presenter. "Exploring dipole blockade using high-n strontium Rydberg atoms." Division of
Atomic, Molecular, and Optical Physics, American Physical Society, Madison, Wisconsin. (Jun
2-6, 2014) With Xinyue Zhang, Shuzhen Ye, Moritz Hiller, Shuhei Yoshida, Joachim Burgdörfer
Presenter. "Formation of heavy-Rydberg ion-pair states in Rydberg atom collisions with
attaching targets." Division of Atomic, Molecular, and Optical Physics, American Physical
Society, Madison, Wisconsin. (Jun 2-6, 2014) With Changhao Wang, Michael Kelley, Sitti
Buathong
Presenter. "Rydberg excitation in a Sr BEC." Division of Atomic, Molecular, and Optical
Physics, American Physical Society, Madison, Wisconsin. (Jun 2-6, 2014) With B. J. DeSalvo, J.
A. Aman, X. Zhang, T. Langin, T. C. Killian
Presenter. "Ultralong-range Rydberg molecules of strontium." 24th International Conference
on Atomic Physics, Washington, D.C.. (Presenter) With B. J. DeSalvo, J. A. Aman, T. C. Kilian
"Creation of quasi-one-dimensional high-n strontium Rydberg atoms." XXVIII International
Conference on Photonic, Electronic and Atomic Collisions, Lanzhou, China. (July 2013)
"Exciting and probing polarized strontium Rydberg atoms." American Physical Society, Division
of Atomic, Molecular & Optical Physics, Quebec City, Canada. (June 2013) With Moritz Hiller,
Shuhei Yoshida, Joachim Burgdorfer, Shuzhen Ye, Xinyue Zhang
"Formation of heavy-Rydberg ion pairs in collisions between Rydberg atoms and attaching
targets." American Physical Society, Division of Atomic, Molecular & Optical Physics, Quebec
City, Canada. (June 2013) With Changhao Wang, Michael Kelley
"Imaging the evolution of an ultracold strontium Rydberg gas." American Physical Society,
Division of Atomic, Molecular & Optical Physics, Quebec City, Canada. (June 2013) With
Xinyue Zhang, Patrick McQuillen, Trevor Strickler, Thomas Killian
"Production of high-n strontium Rydberg atoms." XXVIII International Conference on Photonic,
Electronic and Atomic Collisions, Lanzhou, China. (July 2013) With S. Ye, T.C. Killian, M. Hiller,
S. Yoshida, J. Burgdorfer
"Production of very-high-n strontium Rydberg atoms." American Physical Society, Division of
Atomic, Molecular & Optical Physics, Quebec City, Canada. (June 2013) With Shuzhen Ye,
Xinyue Zhang, Thomas Killian, Moritz Hiller, Shuhei Yoshida, Joachim Burgdorfer
"Stabilizing Bohr wavepackets by electron-electron interaction." American Physical Society,
Division of Atomic, Molecular & Optical Physics, Quebec City, Canada. (June 2013) With M.
Scheucher, D. Wirtitsch, M. Hiller, S. Yoshida, J. Burgdorfer, S. Ye, X. Zhang
"Chaotic energy hopping in bidirectionally kicked Rydberg atoms." 43rd Annual Meeting of the
APS, Division of Atomic, Molecular and Optical Physics, Anaheim, California. (June 2012) With
Korana Burke, Kevin Mitchell, and Shuzhen Ye
"Creating and transporting Trojan wave packets." 43rd Annual Meeting of the APS Division of
Atomic, Molecular and Optical Physics, Anaheim, California. (June 2012) With S. Ye, B. Wyker,
X. Zhang, S. Yoshida, C.O. Reinhold, and J. Burgdörfer
"Heavy-Rydberg ion-pair formation in collisions of Rydberg atoms with attaching targets."
43rd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics, Anaheim,
California. (June, 2012) With Changhao Wang and Michael Kelley
"Ionization of Rydberg atoms in controlled surface electric fields." 43rd Annual Meeting of the
APS Division of Atomic, Molecular and Optical Physics, Anaheim, California. (June 2012) With
Yu Pu
Ionization of kicked Rydberg atoms via a turnstile mechanism. Chaos and Complexity
Conference, Ann Arbor, Michigan. (May 2012) With K Burke, S Ye and B Wyker
"Photoexcitation of high-n, n~300, Rydberg states in the presence of an rf driving field near
the final Kepler frequency." 43rd Annual Meeting of the APS Division of Atomic, Molecular and
Optical Physics, Anaheim, California. (June 2012) With S. Ye, X. Zhang, S. Yoshida, and J.
Burgdörfer
"Decoherence of high-l Rydberg wave packets by collisions and electrical noise." 2011 Annual
meeting of the Division of Atomic, Molecular, and Optical Physics of the American Physical
Society, Atlanta, Georgia. (June 2011) With B. Wyker, S. Ye, T.J. McKinney, C. O. Reinhold, S.
Yoshida, and J. Burgdörfer
"Decoherence of high-n, high-l Rydberg wave packets by electrical noise and collisions."
International Conference on Photonic, Electronic and Atomic Collisions, Queen's University,
Belfast. (July 2011) With S. Yoshida, C. O. Reinhold, J. Burgdörfer, B. Wyker, and S. Ye
"Direct experimental observations of a phase space turnstile in a Rydberg system." 2011
Annual meeting of the Division of Atomic, Molecular, and Optical Physics of the American
Physical Society, Atlanta, Georgia. (June 2011) With Kevin Mitchell, Korana Burke, Shuzen Ye,
and Brendan Wyker
"Electric-field-induced dissociation of heavy Rydberg ion-pair states." 2011 Annual meeting of
the Division of Atomic, Molecular, and Optical Physics of the American Physical Society,
Atlanta, Georgia. (June 2011) With Carlos Reinhold, Shuhei Yoshida, and Changhao Wang
"Field-induced dissociation of Rydberg ion-pair states." International Conference on Photonic,
Electronic and Atomic Collisions, Queen's University, Belfast. (July 2011) With C. O. Reinhold
and S. Yoshida
"Ionization of kicked Rydberg atoms via a turnstile mechanism." 2011 Annual meeting of the
Division of Atomic, Molecular, and Optical Physics of the American Physical Society, Atlanta,
Georgia. (June 2011) With Korana Burke, Kevin Mitchell, Shuzhen Ye, and Brendan Wyker
"Probing and manipulating high-n near-circular Rydberg wave packets." International
Conference on Photonic, Electronic and Atomic Collisions, Queen's University, Belfast. (July
2011) With B. Wyker, S. Ye, S. Yoshida, C. O. Reinhold, and J. Burgdörfer
"Probing surface patch fields with Rydberg atoms." 2011 Annual meeting of the Division of
Atomic, Molecular, and Optical Physics of the American Physical Society, Atlanta, Georgia.
(June 2011) With Yu Pu and Dean Neufeld
"Transporting near-circular Bohr-like wave packets using chirped pulse trains." 2011 Annual
meeting of the Division of Atomic, Molecular, and Optical Physics of the American Physical
Society, Atlanta, Georgia. (June 2011) With S. Yoshida, J. Burgdörfer, C. O. Reinhold, B,
Wyker, and S. Ye
"Transporting near-circular Bohr-like wave packets using chirped sine waves." International
Conference on Photonic, Electronic and Atomic Collisions, Queen's University, Belfast. (July
2011) With B. Wyker, S. Ye, S. Yoshida, C. O. Reinhold, and J. Burgdörfer
"Encoding and decoding information in high-n circular wave packets." 2010 Annual Meeting of
the Division of Atomic, Molecular, and Optical Physics of the American Physical Society,
Houston, TX. (May 2010) With S. Yoshida, C. O. Reinhold, J. Burgdörfer, B. Wyker
"Precise manipulation of Rydberg wave packets." 2010 Annual Meeting of the Division of
Atomic, Molecular, and Optical Physics of the American Physical Society, Houston, TX. (May
2010) With C. O. Reinhold, S. Yoshida, J. Burgdörfer
"Properties of heavy Rydberg ion-pair states formed in collisions between K(np) Rydberg
atoms and attaching targets." 2010 Annual Meeting of the Division of Atomic, Molecular, and
Optical Physics of the American Physical Society, Houston, TX. (May 2010) With M. Cannon, C.
H. Wang
The influence of stray fields on the ionization of Rydberg atoms at metallic surfaces - 2010
Annual meeting of the Division of Atomic, Molecular, and Optical Physics of the American
Physical Society, Houston, TX (with Dennis Neufeld and Yu Pu)
"Creation of non-dispersive Bohr-like wave packets." 40th Annual Meeting of the Division of
Atomic, Molecular, and Optical Physics of the American Physical Society, University of Virginia,
Charlottesville, Virginia. (July 2009) With Jeff Mestayer, B. Wyker, C. O. Reinhold, S. Yoshida,
J. Burgdörfer
"Creation of non-dispersive Bohr-like wavepackets." 26th International Conference on
Photonic, Electronic, and Atomic Collisions, Kalamazoo, Michigan. (July 2009) With J. J.
Mestayer, B. Wyker, S. Yoshida, C. O. Reinhold, J. Burgdörfer
"Formation of heavy Rydberg ion-pair states in collisions of K(np) Rydberg atoms with
attaching targets." 40th Annual Meeting of the Division of Atomic, Molecular, and Optical
Physics of the American Physical Society, University of Virginia, Charlottesville, Virginia. (July
2009) With M. Cannon, C. Wang
"Ionization of Rydberg atoms at metal surfaces." 40th Annual Meeting of the Division of
Atomic, Molecular, and Optical Physics of the American Physical Society, University of Virginia,
Charlottesville, Virginia. (May 2009) With Dennis Neufeld, Yu Pu
"Long-time quantum coherence of near-circular wavepackets." 26th International Conference
on Photonic, Electronic, and Atomic Collisions, Kalamazoo, Michigan. (July 2009) With S.
Yoshida, C. O. Reinhold, J. Burgdörfer, J. J. Mestayer, B. Wyker
"Observation of quantum revivals in very-high-n atoms." 40th Annual Meeting of the Division
of Atomic, Molecular, and Optical Physics of the American Physical Society, University of
Virginia, Charlottesville, Virginia. (July 2009) With Brendan Wyker, J. J. Mestayer, C. O.
Reinhold, S. Yoshida, J. Burgdörfer
"Production of heavy-Rydberg ion-pair states in Rydberg atom collisions." 26th International
Conference on Photonic, Electronic, and Atomic Collisions, Kalamazoo, Michigan. (July 2009)
With M. Cannon, C. Wang
Seminar Speaker
speaker. "Strontium Rydberg atoms: Opportunities and challenges." University of Texas at
Austin, Austin, Texas. (April 2015)
speaker. "Engineering near-circular high-n wavepackets." Durham University, Durham,
England. (February 2011)
speaker. "Ultra-fast physics in the ns regime." Kansas State University, Manhattan, Kansas.
(April 2011)
"Designer atoms: Engineering Rydberg atoms using pulsed electric fields." University of
Belfast, Belfast, Northern Ireland. (May 2009)
"Generation of localized "Bohr-like" wavepackets in high-n Rydberg atoms." Rice University,
Houston, Texas. (September 2009)
"Behavior of Rydberg atoms at metal and semiconductor surfaces." Kansas State University,
Manhattan, Kansas. (April 2008)
"Designer atoms: Engineering Rydberg atoms using pulsed electric fields." Kansas State
University, Manhattan, Kansas. (April 2008)
"Designer atoms: Engineering Rydberg atoms using pulsed electric fields." Northwestern
University, Chicago, IL. (May 2008)
"Designer atoms: Engineering Rydberg atoms using pulsed electric fields." University of
Durham, Durham, England. (March 2008)
Workshops
speaker. "Strontium Rydberg atoms: Opportunities and challenges." Exploratory workshop Rydberg Physics with two-electron systems/University of Hamburg, Hamburg, Germany.
(February 2015)
Supervised Theses & Dissertations
Matthew Cannon, MS The effect of internal energy on the lifetime of SF6- negative ions.
(2007) (Thesis or Dissertation Director)
Dennis Dean Neufeld, MS An ultra-compact retarding potential Mott polarimeter. (2007)
(Thesis or Dissertation Director)
Wei Zhao, PhD Engineering atomic wavepackets in very-high-n Rydberg atoms. (2007)
(Thesis or Dissertation Director)
Hardin Dunham, PhD Angular dependence of xenon Rydberg atom ionization at conducting
and semiconducting surfaces. (2007) (Thesis or Dissertation Director)
Yi Liu, PhD Study of dipole-bound negative ions: formational dynamics and collisional
properties. (2007) (Thesis or Dissertation Director)
Brendan Wyker, M.S. Realization of the Bohr atom. (2008) (Thesis or Dissertation Director)
Jeffery Mestayer, PhD "Rydberg atom wavepacket dynamics in one- and two-dimensions".
(2009) (Thesis or Dissertation Director)
Changhao Wang, M.Sc. Lifetimes of weakly bound heavy-Rydberg ion-pair states formed
through Rydberg atom collisions with attaching targets. (2010) (Thesis or Dissertation
Director)
Matt Cannon, Ph.D. Collisional formation of heavy Rydberg ion-pair states. (2010) (Thesis or
Dissertation Director)
Dennis Neufeld, Ph.D. Interaction of xenon Rydberg atoms with conducting surfaces: the
effects of stray fields. (2010) (Thesis or Dissertation Director)
Brendan Wyker, PhD High angular momentum Rydberg wave packets. (2011) (Thesis or
Dissertation Director)
Shuzhen Ye, MS Chaotic ionization of a Rydberg atom subjected to alternating kicks. (2011)
(Thesis or Dissertation Director)
Xinyue Zhang, MS Creating strontium Rydberg atoms. (2013) (Thesis or Dissertation Director)
Yu Pu, PhD Ionization of Rydberg atoms at patterned electrode arrays. (2013) (Thesis or
Dissertation Director)
Shuzhen Ye, PhD Experimental study of potassium and strontium Rydberg atoms - chaotic
ionization, quantum optical phenomena and multiphoton excitation. (2014) (Thesis or
Dissertation Director)
Michael Kelley, MS Dynamics of ion-pair formation in K(14p,20p)-SF6, CCl4 collisions. (2014)
(Thesis or Dissertation Director)
Changhao Wang, PhD Dynamics and dissociation of collisionally formed heavy Rydberg ion
pair states. (2015) (Thesis or Dissertation Director)
Sitti Buathong, MS Studies of intermediates created via dissociative electron attachment
through heavy-Rydberg ion-pair state formation in Rydberg atom collisions. (2015) (Thesis or
Dissertation Director)
Gavin Fields, MS Studies with strontium Rydberg atoms. (2015) (Thesis or Dissertation
Director)
Xinyue Zhang, PhD Probing electron-electron and atom-atom interactions using Rydberg
atoms. (Thesis or Dissertation Director)
Roger Ding, MSc Narrow line cooling of 84Sr. (Thesis or Dissertation Director)
Awards, Prizes, & Fellowships
Outstanding Associate - Jones College, Jones College, Rice (Spring 2013)