Download Projects available in 2017

Projects available in 2017
A short description of the work carried out by the different Research Groups is now given,
followed by a listing of project titles, supervisor contact details and a paragraph describing
each of the projects. The titles represent only some of the opportunities available for research
projects and you are welcome to explore other possibilities in your field of interest with
potential supervisors in the School of Physics.
It is very important to choose a project and supervisor to suit your interests and skills. You are
strongly encouraged to have discussions with several possible supervisors before making a
decision. Speaking to current Honours and postgraduate students will also give you valuable
feedback. The Web of Science, accessible from the Library website, will give you information
on the research activity of the School's academics. You should also read the Research pages
on the School's website (http://www.physics.usyd.edu.au/research.html) for more information
on the different areas that are currently being researched.
Students should decide upon projects as early as possible, and must arrange a supervisor
and project prior to applying for Honours. You should aim to start 3 weeks before the start of
lectures. This will enable you to get your project under way before lectures and assignments
compete for your time.
Students should make certain that their proposed supervisor will not be absent for protracted
periods during semester, unless an associate supervisor is also involved. These issues will
need to be formally settled when you submit your Research Plan, two weeks after the start of
your first Semester as an Honours student.
Honours students are expected to continue working in their Research Groups during
the normal undergraduate vacation periods, except for the designated rest period for
students commencing in the July Semester (see Important Dates section).
Overview of Research Themes
The School of Physics is large and diverse, and offers a broader range of research areas in
Physics than any other university in Australia.
Research in the School is often presented in terms of Research Themes, listed below:
Research Projects in Astronomical and Space Physics ......................................................... 2
Research Projects in Atomic Molecular and Plasma Physics .............................................. 14
Research Projects in Biological, Biomedical and Medical Physics....................................... 17
Research Projects in Complex Systems.............................................................................. 18
Research Projects in Condensed Matter Physics ................................................................ 30
Research Projects in Particle Physics ................................................................................. 33
Research Projects in Photonics and Optical Science .......................................................... 39
Research Projects in Physics Education ............................................................................. 50
Research Projects in Quantum Physics and Quantum Information ..................................... 51
Theoretical Physics Group .................................................................................................. 56
Details of these research activities can be found at:
http://sydney.edu.au/science/physics/research/index.shtml
Research Projects in Astronomical and Space Physics
Projects for 2017 by research themes
Research Projects in Astronomical and Space Physics
Title of Project: How does gas get into galaxies?
Supervisor: Prof. Joss Bland-Hawthorn (Director of SIfA)
Co-supervisor: Thorsten Tepper-Garcia (Research Fellow)
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Galaxies need gas to form stars and this is how we see them through their starlight. We
see gas clouds all around our Galaxy, some of them falling towards us. But when we
simulate on a computer how the gas falls into a galaxy, it should break up due to the
galaxy’s hot “atmosphere” and appear invisible to our telescopes, rather like a satellite
falling towards Earth. This is a longstanding mystery. We have produced state of the art
simulations of gas
clouds embedded in
mysterious dark matter
halos which can help to
keep the clouds
together. Is this the
solution to the mystery,
that the many infalling
clouds we see are
embedded in dark
matter, or is it
something else? (To
date, all the dark
haloes we know of
have stars in them, and never gas by itself. There is a real potential for discovery here.)
We have begun to explore the effect of Galactic magnetic fields in confining the gas. We
propose to compare our simulations to new observations of these gas clouds. The student
will learn how to extract objects from a simulation and render them in a way that can be
compared to real observations. Our goal is to publish a research paper in the Astrophysical
Journal.
INSET: Cold gas clouds in the Galactic halo moving towards (blue) and away (red) from
us.
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Research Projects in Astronomical and Space Physics
Title of Project: Astrocombs and microspectrographs for detecting oscillations in
nearby stars
Supervisor: Prof. Joss Bland-Hawthorn (Director of SIfA)
Co-supervisor: Dr. Sergio Leon-Saval, Prof. Tim Bedding
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The astrophotonics labs are prototyping a new device that generates thousands of faint
monochromatic lines. We can use this device
with a small telescope to observe oscillations in
nearby stars with one of our new-generation
microspectrographs. We can detect tiny
changes in the star’s light and determine if the
star is oscillating or has a planet in orbit about it
(see inset). We have preliminary data taken with
the School of Physics Rooftop Telescope
(SPORT) to detect solar oscillations. In the first
part of this project, we will use MATLAB to
analyse our data to see how small a signal we
can detect. Depending on the outcome, we will
consider taking our microspectrograph to a much larger telescope at Siding Spring
Observatory. The longer-term plan is to roll this technology into a full-blown planet finder
on Australia’s Giant Magellan Telescope. Our goal is to publish a paper in Optics Express.
Title of Project: The Galaxy in three dimensions
Supervisor: Prof. Joss Bland-Hawthorn (Director of SIfA)
Co-supervisor: Sanjib Sharma (Research Fellow)
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
One of the most amazing projects in astronomy today is ESA’s Gaia satellite (see below)
which is mapping the motion and location of two billion stars, about 1% of the Galaxy. ESA
will release the first data in two weeks. Our goal is to construct the first 3D pictures of the
Galaxy to compare with numerical models derived from supercomputer simulations. We
will search for ancient star streams which are thought to be due to small galaxies falling in
over billions of years. The number of streams in the Galactic halo will be compared with
cosmological simulations. Just how did the Galaxy come together? Are small galaxies still
falling in today or was it all in the distant past? Our goal is to publish a research paper in
the Astrophysical Journal.
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Research Projects in Astronomical and Space Physics
Title of Project: Suppression of star formation in massive galaxies by relativistic jets
Supervisor: Prof. Scott Croom
Co-supervisor: Prof. Elaine Sadler
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Almost all galaxies contain super-massive black holes (a million to a billion times as
massive as the Sun) at their centres. The most massive galaxies are found to contain only
old stars, with little ongoing star formation. The lack of ongoing star formation is thought to
be due to the heating of gas in the galaxies by relativistic jets from a super-massive black
hole. These jets are clearly visible in radio frequency observations. We have built a major
new survey of radio emitting jets in galaxies over a large range in cosmic time. In this
project we will use multi-band imaging to model the emission of these galaxies, at radio,
infrared, optical and ultra-violet wavelengths. Using this approach we hope to clearly
quantify the amount of residual star formation in massive galaxies and directly test the
radio feedback model.
Title of Project: Location, location location: where are the most active supermassive black holes?
Supervisor: Prof. Scott Croom
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
While most or all galaxies have super-massive black holes at their centres, only a small
fraction of these are actively accreting gas, and shining brightly as active galactic nuclei
(AGN). We still have a relatively poor understanding of what event in a galaxy’s life
causes its black hole to start an accretion episode. Is this via internal processes, within the
galaxy? Or is the accretion driven by external influences? The large-scale external
environment is thought to be a major factor in disturbing galaxies and triggering the flows
of gas that can be accreted onto black holes. In this project you will use the latest major
galaxy survey carried out on the Anglo-Australian Telescope, the Galaxy And Mass
Assembly (GAMA) survey to find the location of active galaxies. These data will be used to
answer question such as: are galaxies with active black holes more likely to be in groups
with other galaxies? Are galaxies with active black holes in the centres of groups?
Title of Project: Setting the clock on black hole feedback
Supervisor: Prof. Scott Croom
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Accretion onto super-massive black holes is thought to profoundly influence the growth of
galaxies, supressing star formation. Bizarrely, it has been hard to find direct evidence of
this influence in galaxies where the central super-massive black hole is accreting at its
highest rate. The fundamental reason for this is that the time-scale of accretion onto black
holes can be very different to the time-scale for star formation. In this project we will use
multi-wavelength data on local galaxies from the recent Galaxy And Mass Assembly
(GAMA) to measure the star formation rate time-scale over a range of scales from a few
million years to a billion years. We will directly compare the star formation time-scales
derived from galaxies with and without active black holes to measure the impact of
feedback from the black holes.
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Research Projects in Astronomical and Space Physics
Title of Project: Testing dark matter models using galaxy spins
Supervisor: Prof. Scott Croom
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Dark matter remains a mystery. Although various different arguments require that the
dominant mass component in the Universe is not baryonic, the specific type of matter
remains unknown. The standard model currently assumed is that dark matter is a cold
(non-relativistic) massive particle. However, this predicts more small-scale structure than
is currently observed. An alternative is warm dark matter, which erases some of the
small-scale structure. One of the usual ways to test this is to look at the number of
galaxies as a function of mass. Cold dark matter predicts we should have many more low
mass galaxies. The challenge is that feedback from the process of galaxy formation can
also change the number of galaxies that form (or rather the number of stars that form in
them). A cleaner way to carry out this test is to measure the mass of galaxies more
directly, which can be done using the motions of gas and stars. In this project we will use
the rotations of galaxies from the new University of Sydney led SAMI Galaxy Survey to
measure the distribution of galaxies as a function of rotational velocity and mass, and
compare them to predictions of cold dark matter and alternative warm dark matter models.
Title of Project: The best way to measure environment
Supervisor: Prof. Scott Croom
Co-supervisor: Dr. Sarah Brough (Australian Astronomical Observatory)
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Galaxies are found in a wide range of environments, from hamlets where they are a very
long way from their neighbours to cities where they live cheek-by-jowl with thousands of
other galaxies. Unfortunately there are many different ways of measuring that
environment, each of which gives a slightly different picture of what effect that
environment has. The aim of this project is to use data from the very large new Galaxy
And Mass Assembly (GAMA) survey to determine the environment measure that optimally
characterises a galaxy's true environment. This project will provide invaluable skills in the
mathematical analysis of large sets of data. Students co-supervised by AAO staff are
eligible to apply for the AAO Honours Scholarship of $5000:
http://www.aao.gov.au/science/research/students/phd-and-honours
Title of Project:Getting the perfect 3-D picture
Supervisor: Prof. Scott Croom
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Optimal image reconstruction is of fundamental importance in a number of fields including
medicine geology and astronomy. As data sets become larger and more complex, with
higher dimensionality, it is more important than ever to get the best use of the data. In this
project we will bring together some of the latest methods in image reconstruction, such as
Gaussian processes, and apply them to state of the art 3-dimensional astronomical data
sets (taken from the SAMI Galaxy Survey being led by the University of Sydney). We will
aim to modify general techniques to take into account practical effects (such as
atmospheric distortion, under-sampling and non-uniform sampling) and find optimal
solutions to the image reconstruction problem. We will then measure fundamental
properties of the galaxies in the reconstructed galaxy images, such as the age and heavy
element content of the stars in the galaxies.
This project would suit a student with some prior programing background and could be
carried out in Python, Matlab or some other suitable language.
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Research Projects in Astronomical and Space Physics
Title of Project: Precision spectroscopy of distant galaxies
Supervisor: Prof. Scott Croom
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Fundamental to our ability to carry out precision spectroscopy is the need to accurately
quantify the intrinsic resolution of any spectrograph. In almost all cases, particularly when
targeting distant galaxies, there is an assumption of constant resolution and that the line
profile provided by the spectrograph is Gaussian in nature. When we want to probe the
internal dynamics of a galaxy (for example to measure the total mass, including dark
matter) we often need to work near the resolution limit of spectrographs and incorrect
modelling of the instrumental resolution biases our results often making it impossible to
measure the mass density in the outer parts of disk galaxies. To address this problem we
need a more precise model of spectrograph resolution that is allowed to vary with both
time and wavelength. In this project the student will develop a set of new approaches to
precisely defining instrumental resolution, using a range of data taken from the Sydney led
SAMI Galaxy Survey. The new models of resolution will be used to provide improved
measurements of galaxy dynamics and mass.
Title of Project: Bell’s spaceship paradox: Just what do you see?
Supervisor: Geraint Lewis
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Bell’s spaceship paradox concerns the separation between two spaceships accelerating to
relativistic speeds, seemingly in contradicting the notions of length contraction. In this
project, we will examine just what observers on the rockets actually see during the period
of acceleration, and see how this relates to the notion of length contraction and the
meaning of the paradox itself. This will require learning the language of special relativity,
and the mathematics of accelerated motion, as well as the motion of light rays and the
meaning of observation at relativistic speeds. The project will involve mathematical
manipulation and numerical integration within a package such as Matlab.
Title of Project: The last thing you see!
Supervisor: Geraint Lewis
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Black holes possess some very strange properties, with a one way “event horizon” which
prevents you from leaving. But once below the event horizon, how much of the external
universe do you see pass before you meet your demise? In this project, you will
numerically integrate the paths of infalling observers, including those possessing
accelerating rocket packs, and calculate their intersection with inward falling light rays. By
adjusting the rocket thrust, you will see who experiences the most “proper time” as they
fall, and identify who sees the most external time pass.
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Research Projects in Astronomical and Space Physics
Title of Project: Hydrogen, Helium & the Big Bang
Supervisor: Geraint F. Lewis
Co-supervisor: Luke Barnes
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The mix of hydrogen and helium in the universe is highly dependent upon a period called
“freeze-out” which fixes the relative number of protons and neutrons before
nucleosynthesis begins. In this project, we will consider the influence of two fundamental
quantities in the universe, namely the mass difference between protons and neutrons, and
the expansion in the early epoch of the universe, and examine their influence on the
subsequent nucleosynthesis. The project will require experience with the C programming
language, as well as a program for MATLAB for plotting.
Title of Project: Space-ready micro-spectrographs for Cubesat platforms
Supervisor: Sergio Leon-Saval
Co-supervisor: Chris Betters
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Classical Fourier transform spectrometers (FTS) must translate a mirror while monitoring
the interference pattern to make measurements. In this project we will study and develop a
spatial heterodyne spectrometer that replaced the moving mirrors of a Michelson
interferometer with reflective diffraction gratings. This should allow a spectrum to be
recorded in a fixed format (no moving parts) that will be more suitable for deployments in
harsh environments (i.e. CubeSat’s in space). The project will involve both computer aided
optical design (using Zemax) and building the optical instrument in the lab. This project is
likely to included the development of 3D printed components with the in-house facility. The
final aim of the project will be to test the developed spectrograph in space environments
(such as high vacuum) with our research collaborators at the Australian National
University.
Title of Project: All-fibre adaptive optic system for optical beam shaping
Supervisor: Sergio Leon-Saval
Co-supervisors: Chris Betters / Barnaby Norris
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Photonic lanterns- efficient multimode to single-mode convertors devices are a very
fascinating technology currently used in Astronomy and Telecommunications. Those
optical devices convert light from a set of co-propagating optical modes with different
spatial electromagnetic distributions into a set of identical optical modes at different fibre
ports and vice versa. The unique properties of photonic lanterns also enable dynamic
control of the beam intensity and phase, which has enormous potential for advanced highspeed adaptive optics beam shaping. This project will study an alternative approach to
spatial-mode control using active feedback to stabilize and shape the output beam of a
multimode fibre by appropriately launching the correct superposition of input modes in both
phase and amplitude. Hence, achieving an all-fibre based AO system that preconditions
the input to achieve a desired beam shape and phase on the output.
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Research Projects in Astronomical and Space Physics
Title of Project: Next generation optical fibres for extremely large telescopes
Supervisor: Sergio Leon-Saval
Co-supervisor: Joss Bland-Hawthorn
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Next generation extremely large telescopes (ELTs) will have mirrors in the order of 30 to
40 meters in diameter. ELTs will address the major science issues of the next two
decades, enabled by huge gains in sensitivity resulting from collecting areas that are more
than 25 times larger than those of the largest telescopes today. These larger collecting
areas represent a challenge for today’s standard multimode fibres used in astronomy. This
project will focus in fabrication and understanding of the next generation multimode fibres
for astronomy: Multimode Fibre Slicers (MFS) and multimode to multimode fibre
converters.
Title of Project: Optical jigsaw puzzles with fibre optics
Supervisor: Sergio Leon-Saval
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Multimode to single-mode convertors fibre devices are a very fascinating technology
currently used in Astronomy and Telecommunications. The fascinating nature of their
behaviour is still under study. Those optical devices convert light from a set of copropagating optical modes with different spatial electromagnetic distributions into a set of
identical optical modes at different fibre ports and vice versa. This project will aim to unveil
the ways on which this optical jigsaw puzzle behaves. The project will involve theoretical
analysis of the optical devices and a strong experimental component. We will interrogate
those devices by using state of the art photonic components such as spatial light
modulators (SLM), lasers, polarisers, optical fibres and light detectors.
Title of Project: Searching for outflows in the youngest radio galaxies
Supervisor: Dr. Elizabeth Mahony
Co-supervisor: Prof. Elaine Sadler, A. Prof. Scott Croom
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Active Galactic Nuclei (AGN) are amongst the most luminous and energetic objects in the
Universe and are known to play an important role in regulating the growth of galaxies. The
tight correlations observed between the central supermassive black hole and the host
galaxy is generally attributed to fast outflows of gas being driven from the nucleus, halting
both further accretion onto the black hole and star-formation within the galaxy. Using
optical data obtained from the 3.6m NTT telescope in Chile, this project aims to detect
these fast outflows in young radio galaxies by searching for broad emission lines out to
redshifts of z=0.7.
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Research Projects in Astronomical and Space Physics
Title of Project: Measuring the rotation of stellar cores with asteroseismology
Supervisor: Simon Murphy
Co-supervisor: Tim Bedding
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Despite great advances in astrophysics in the past century, open questions in the physics
of stellar models remain. One of these questions concerns the rotation of stellar cores,
which until recently were impossible to observe. Now, asteroseismology - the study of
stellar oscillations - has opened a window to the stellar interior with sensitivity to the interior
rotation rates. The results are remarkable. The rotation of red giant stars is two orders of
magnitude different from what was expected from theory, and main sequence stars rotate
almost rigidly.
Only a handful of stars have had their rotation profiles measured, and all of these in the
past few years. The breakthroughs have come from ultra-precise data from the Kepler
Space Telescope, which monitored the brightnesses of over 150,000 stars simultaneously.
Stellar oscillations cause small changes in brightness that can be studied by Fourier
transforms of the light curve. This project will examine the rotation profiles of the most
promising Kepler targets to uncover the next surprises.
Title of Project: Characterizing Stars observed by the NASA K2 Mission with
Skymapper
Supervisor: Simon Murphy
Co-supervisor: Tim Bedding
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Following the failure of two reaction wheels on board NASA's planet-hunting Kepler space
telescope, the spacecraft was repurposed as the "K2 Mission" to observe different fields
along the ecliptic plane. The brand new K2 mission has already collected brightness
measurements of over 100,000 stars to detect transiting planets as well as to study
rotation and oscillations of stars. However, the characteristics of many of the targets that
are observed by K2 are uncertain. The Australian Skymapper telescope has recently
released data for a large area in the southern hemisphere, including many fields observed
by K2. The project will involve cross-matching the Skymapper catalog with the K2 target
list, investigating which Skymapper data products are most sensitive to measure stellar
sizes, and improving the characterization of K2 targets (including host stars and their
planets).
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Research Projects in Astronomical and Space Physics
Title of Project: Extreme events: exploring the transient universe with the MWA
Supervisor: Tara Murphy
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area :
Some of the most extreme events in the Universe occur when black holes form, or merge
with each other, or when stars move too close to a black hole and get sucked in. In each of
these cases strong bursts of electromagnetic radiation are released, which we detect on
Earth as ’transient’ radio emission. Not only are these events interesting in their own right,
they also serve as an astronomical laboratory for exploring physics in extreme conditions.
Until now we have had a limited ability to find and study these objects as they appear and
disappear on short timescales.
Radio astronomy is undergoing a revolution, with new telescopes able to conduct massive
all-sky surveys on a regular basis, allowing us to discover ’transient’ radio sources. In this
project you will work with data hot off the press from the Murchison Widefield Array (MWA), a
low frequency radio telescope in Western Australia. You will have access to this unique (and
completely unexplored) dataset to look for transient and highly variable radio sources, and
then draw on multi-wavelength data and observations from other telescopes to identify what
these sources are.
Title of Project: Exploring the high-frequency radio sky
Supervisor: Prof. Elaine Sadler, Dr Tara Murphy
Co-supervisor:
Email Contact: Prof. Elaine Sadler, [email protected]
Brief Description of Project or Project Area :
Studying the radio sky at high frequencies (20 - 100 GHz) can provide unique physical
insights into both nearby and very distant astrophysical objects. The recently-completed
Australia Telescope 20GHz (AT20G) survey provided the first large and uniform sample of
high-frequency radio sources, and we are offering two projects which use the AT20G data to
explore very different aspects of the high-frequency radio sky.
One project is a study of compact regions of ionized hydrogen within our own Milky Way
galaxy, where radio observations allow us to penetrate the intervening clouds of dust and
pinpoint the locations in which unusually massive stars are currently forming. The second
project is a study of much more distant galaxies, in which the observed radio emission is
powered by the accretion of gas onto a black hole at the galaxy’s centre. The aim here is to
measure how the radio emission varies with time, and to find out whether these rare highfrequency radio sources signal the ’switching on’ of a powerful radio galaxy or quasar in the
distant universe.
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Research Projects in Astronomical and Space Physics
Title of Project: The Bright Radio-Source Population at 150 MHz
Supervisor: Prof. Elaine Sadler, Dr Tara Murphy
Co-supervisor:
Email Contact: Prof. Elaine Sadler, [email protected]
Brief Description of Project or Project Area :
In this project, you will be analysing data from the Murchison Widefield Array (MWA), a
powerful new low-frequency radio telescope which has just started operation in a remote
region of Western Australia. The MWA has a wide field of view, allowing it to image the
whole southern sky at frequencies of 80-230 MHz.
In this project you will investigate some of the brightest low-frequency radio sources
revealed by the MWA, using a combination of radio and optical data to identify the
dominant physical mechanisms which produce the radio emission. You will be working
within a lively and dynamic research group at SIfA, and may also have the opportunity to
visit the MWA group in Perth to present and discuss your research results.
Title of Project: Hunting for dark matter with SAMI
Supervisor: Dr Nicholas Scott
Co-supervisor: A Prof Scott Croom
Email Contact: [email protected]
Brief Description of Project or Project Area :
Dark matter is the dominant form of matter in the Universe, yet its nature and origin remain
almost completely unknown. The majority of our knowledge of dark matter comes from
studying its gravitational effects on the stars and gas in galaxies.
The SAMI Galaxy Survey is a large 3D spectroscopic survey of nearby galaxies, led by
The University of Sydney. SAMI is collecting maps of the motions of stars for several
thousand galaxies. This project will first use models of galaxies to test how well SAMI
observations can constrain the dark matter content of galaxies. Then, by applying these
models to real data, the project will measure the dark matter content for the largest sample
of galaxies to date, and explore how the dark matter fraction varies with other galaxy
properties. This will provide a new, fundamental constraint on current theories of galaxy
evolution.
Title of Project: Extragalactic archaeology – untangling the histories of nearby
galaxies
Supervisor: Dr Nicholas Scott
Co-supervisor: A Prof Scott Croom
Email Contact: [email protected]
Brief Description of Project or Project Area:
The past histories of galaxies are encoded in their stellar populations, though extracting
and interpreting this information is challenging. Using modern spectral synthesis
techniques, the star formation history of a galaxy can be inferred from its observed
spectrum. How the ages and chemical compositions of stars vary throughout a galaxy can
be the key to unlocking billions of years of galactic history.
The SAMI Galaxy Survey is a large 3D spectroscopic survey of nearby galaxies, led by the
University of Sydney. 3D data ‘cubes’ allow spectra to be measured at multiple points
across a galaxy, allowing the star formation histories of galaxies to be mapped for
thousands of objects for the first time.
This project will test competing techniques for extracting star formation histories from
galaxy spectra, identifying the best approach to take for the SAMI Galaxy Survey. This
technique will then be applied to real SAMI data to infer the formation history of thousands
of nearby galaxies.
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Research Projects in Astronomical and Space Physics
Title of Project: Planet Hunting with Large Telescopes
Supervisor: Prof Peter Tuthill
Co-supervisor: Barnaby Norris
Email Contact: [email protected]
Brief Description of Project or Project Area:
The direct detection of light from exoplanets remains among the signature quests of modern
astronomy, and indeed within all of contemporary science. Although indirect techniques (such
as radial velocity searches) have delivered nearly 1000 planets over the last 20 years, only
advanced imaging techniques able to record direct light from the planets themselves offer a
pathway to future visionary telescopes able to characterize the chemistry of exoplanetary
atmospheres for habitability.
For this project you will analyze (and hopefully participate in taking) data from some the
world's large telescopes such as Keck, Subaru, VLT, LBT and Gemini. Advanced imaging
techniques pioneered by our group have delivered the first ever detections of exoplanets at
the epoch of their birth. The key aspect of the high angluar resolution images you will
produce is that they reveal orbital motion, and hence masses and densities, of the exoplanets
or brown dwarfs being studied.
Title of Project: The James Webb Space Telescope Interferometer
Supervisor: Prof Peter Tuthill
Co-supervisor: Barnaby Norris
Email Contact: [email protected]
Brief Description of Project or Project Area:
The James Webb Space telescope (JWST) is an $8 billion dollar space mission intended to
inherent the mantle from the Hubble Space Telescope as the predominant observatory for
optical/infrared astronomy into the 21st century. After its launch later this decade, the mission
will deploy a 6.5m primary mirror with passive cooling out at the L2, the second Lagrangian
stability point. One of the key science niches targeted by this mission is the discovery of
exoplanets.
For this project you will work on a dedicated interferometer developed at the University of
Sydney which will fly aboard the NIRISS instrument (we are the only Australian group to
design instrumentation for this mission). The project will explore the JWST space
interferometer to derive primary performance metrics, and generate a full experimental
simulation of the experiment incorporating a host of real-world sources of error and
imperfection. These studies will be based both on numerical simulations and results from
optical testbeds in Sydney, Baltimore and Ball Aerospace (Denver). The outcome will be an
optimized observational campaign for flight deployment.
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Research Projects in Astronomical and Space Physics
Title of Project: Galactic big game: hot massive stars and supergiants
Supervisor: Prof Peter Tuthill
Co-supervisor: Barnaby Norris
Email Contact: [email protected]
Brief Description of Project or Project Area:
In the galactic eco-system, the hot massive luminous stars at the top exercise an outsize
influence on the evolution of the galaxy. Exceeding our own sun by factors of five in
temperature, fifty in mass, and fifty-thousand in luminosity, these T-Rex's of the stellar
kingdom dominate many aspects of the physics of the galaxy, despite being outnumbered
thousands to one by more normal stars. When we look at a distant galaxy, the light we see
mostly comes from a handful of these overachievers, outshining the teeming multitudes of
low-mass stars.
For this project you will study these rare and exotic stars with unprecedented resolution, for
the first time revealing structures at the critical scale of the stellar photospheres themselves.
Taking your own data with the CHARA array in Southern California, the project will be the first
to separate constituents of these stellar systems for detailed study, revealing the basic
physics of masses and stellar atmospheres as well as exotic mass loss processes which are
critical to governing the eventual fate of these stars in Supernova explosions.
Title of Project: Astrophotonics for exoplanetary discovery
Supervisor: Prof Peter Tuthill
Co-supervisor: Barnaby Norris, Nick Cvetojevic
Email Contact: [email protected]
Brief Description of Project or Project Area:
One of the most audacious goals in all of modern science is the discovery and
characterization of extra-solar planets, and in particular, the identification of potential new
worlds suited to the support of a flourishing biosphere. However, despite much progress,
there remain formidable technological hurdles in the construction of any telescope truly
capable of the revealing the physics and chemistry of an exoplanetary atmosphere.
For this project you will work on a revolutionary new concept, which marries recent advances
in photonic control and manipulation of starlight together with leading edge new imaging
technologies from astronomy such as adaptive optics and interferometry. The final goal will
be the design and specification of an infrared nulling interferometer, capable of rejecting the
overwhelming glare from the parent star, thereby enabling detailed study of the faint
planetary light. This project can involve both instrument development and design in the new
SAIL laboratories here at Physics, and/or more theoretical work in simulation and data
analysis.
Honours Project Offering 2017 v.1.1
13
Research Projects in Atomic Molecular and Plasma Physics
Research Projects in Atomic Molecular and Plasma Physics
Title of Project: Deposition of robust functionalized coatings on pulse-biased
substrates
Supervisor: Dr Behnam Akhavan
Co-supervisor: Prof. Marcela Bilek
Email Contact: [email protected]
Brief Description of Project or Project Area:
Plasma polymerization is a versatile surface engineering
process capable of depositing ultra-thin functionalized
films for a range of applications such as biomaterials for
cell attachment and immobilization of enzymes and
proteins. In this technology, the desired monomer is
initially converted into vapour under a low pressure, and it
is subsequently excited into the plasma state using an
electric field. The recombination of active species takes
place on any surface exposed to the plasma, thus forming
a thin layer of functionalized plasma polymer coating.
Production of plasma polymer films that are high in
functional group(s) yet stable in body fluids is, however, challenging. This research will be
focused on the production of robust functionalized plasma polymer films through judicious
choice of plasma deposition parameters. The student will obtain experience in laboratory
experiments including both fabrication and characterization of novel engineered surfaces.
This research is suitable to be continued as a subsequent PhD project. Applicants of this
project will be eligible to apply for scholarship funding tied to the project.
Title of Project: Development of plasma activated coatings on particulate surfaces
Supervisor: Dr Behnam Akhavan
Co-supervisor: Prof. Marcela Bilek
Email Contact: [email protected]
Brief Description of Project or Project Area:
A plasma activated coating (PAC) is deposited
onto substrates via excitation of a precursor
gas, e.g. acetylene, in a plasma deposition
system consisting of an RF electrode and a
pulsed voltage source. PAC facilitates the
immobilization of bioactive molecules on the
surface owing to highly reactive radicals
generated in the coating. While we have
successfully fabricated such surfaces onto 2-D
substrates, there is great potential to further
develop this knowledge for the coating of particulate materials. In comparison with 2-D
substrates, plasma polymer-coated 3-D surfaces are of more interest in real-world
applications such as protein adsorption/separation and removal of toxic matter from water.
This project will involve designing an agitation system to retrofit an existing plasma
deposition system followed by the deposition of plasma activated coatings onto model
particulate substrates. The student will obtain experience in laboratory experiments
including both fabrication and characterization of novel engineered surfaces. This
research is suitable to be continued as a subsequent PhD project. Applicants of this
project will be eligible to apply for scholarship funding tied to the project.
Honours Project Offering 2017 v1.1
14
Research Projects in Atomic Molecular and Plasma Physics
Title of Project: Fabrication of oxidized sulphur-containing films through a plasmaassisted approach
Supervisor: Dr Behnam Akhavan
Co-supervisor: Prof. Marcela Bilek
Email Contact: [email protected]
Brief Description of Project or Project Area:
Surfaces containing oxidized sulfur species [−SOx(H)] are
of great interest in a number of critical applications
including biomaterials, fuel cells, and water purification.
SOx(H)-containing surfaces show remarkably high blood
compatibility because of their decreased platelet adhesion
and anti-inflammatory properties. These surfaces also
exhibit enhanced ionic conductivity, which makes them
excellent candidates for proton-exchange membranes.
This project will look into the fabrication of such surfaces
using a plasma deposition system consisting of an RF
electrode and a pulsed voltage source for biasing the
substrates. Precursor gas mixtures and deposition parameters will be tuned to achieve
desirable sulphur-containing plasma polymer films for the above-mentioned applications.
The student will obtain experience in laboratory experiments including fabrication and
characterization of novel engineered surfaces. This research is suitable to be continued as
a subsequent PhD project. Applicants of this project will be eligible to apply for scholarship
funding tied to the project.
Title of Project: Plasma ion implantation treatment of porous polymeric materials
Supervisor: Dr Behnam Akhavan
Co-supervisors: Prof. Marcela Bilek, Dr Alexey Kondyurin, Dr Elena Kosobrodova
Email Contact: [email protected]
Brief Description of Project or Project Area:
Plasma immersion ion implantation (PIII)
results in the creation of highly reactive
radicals on targeted polymeric materials.
These reactive radicals are excellent sites
for the immobilization of bioactive
molecules. Membranes and porous
materials treated via this technique will be
of interest for a number of applications
including cell culture, tissue engineering and protein adsorption/separation. For such
applications, reactive sites should ideally be generated not only onto the surface of a
membrane, but also onto the entire internal network of pores. The development of these
membranes requires specific reactor designs and geometries that are already available in
our laboratories. This project will involve PIII treatment of porous materials under
optimized conditions followed by immobilization/separation of targeted biomolecules. The
student will obtain experience in laboratory experiments including fabrication and
characterization of novel engineered surfaces. This research is suitable to be continued as
a subsequent PhD project. Applicants of this project will be eligible to apply for scholarship
funding tied to the project.
Honours Project Offering 2017 v.1.1
15
Research Projects in Atomic Molecular and Plasma Physics
Title of Project: Surface enhanced fusion reactions
Supervisor: Joe Khachan
Co-supervisor: Oliver Warschkow
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Experiments that produce table-top nuclear fusion, known as inertial electrostatic
confinement (IEC), use electric fields to heat and confine ions. The small scale of such a
device holds great potential for producing small and portable fusion energy devices –
unequaled by any contemporary device. This type of fusion is achieved by focusing ions to
a central point using spherical electrostatic grids. In recent experiments, we have found that
a substantial part of this fusion occurs at the grid wires and not at the focal point. Further
investigations have shown that fusion probability at a metal surface can be enhanced by
embedding the hydrogen isotopes in the crystal lattice and relying on the electron density
of states around the fusion ion nucleus to shield its Coulomb potential. Any incoming
energetic ion approaches the nucleus more closely than an unshielded nucleus. This has
the effect of increasing the fusion cross-section (or probability) and therefore can produce
higher fusion rates than collisions with the bare nucleus. This is quite a new field of research
and the aim is to use computational methods to investigate the enhancement of fusion
cross-sections of light hydrogen isotopes embedded in the crystal lattice of various metals.
An enhancement in fusion cross-section by three orders of magnitude places this approach
in contention as a possible energy producing process. There are experimental results that
indicate this is a valid approach. There are also experiments being carried in the School that
clearly show the importance of the nature of the metal surface. The tool of this project that
you will need to master, with guidance, is known as density functional theory, which is a
computational approach to solid state physics. Using density functional theory, you can
predict both the binding sites of hydrogen atoms within the crystal lattice, and the electron
density that surrounds the atom. This in turn allows you to estimate the Coulomb screening,
and thus potentially the fusion cross-section.
Honours Project Offering 2017 v.1.1
16
Research Projects in Biological, Biomedical and Medical Physics
Research Projects in Biological, Biomedical and Medical Physics
Title of Project: Modeling of sodium channels
Supervisor: Serdar Kuyucak
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area :
Sodium channels play important roles in many aspects of cellular function such as
propagating the action potential in nerves. However, due to lack of any molecular structure,
progress in the field of sodium channels has been very slow. After decades of trials, the first
crystal structure of a bacterial sodium channel has finally been determined (Nature 475, 353
(2011)). The aim of this
project is to improve the mammalian homologue from this crystal structure, and perform
molecular dynamics simulations to investigate the ion permeation and selectivity mechanisms
in sodium channels. This will lay the foundations for future work on medical aspects of
sodium channels (e.g., how neurological diseases are caused by dysfunctional channels),
and pharmacology (e.g., targeting diseased sodium channels with drugs to modulate their
behaviour).
Title of Project: Developing drugs using toxin peptides from plants
Supervisor: Serdar Kuyucak
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area :
Many toxins bind to ion channels affecting their normal operation. Because of their high
affinity and specificity, toxins provide ideal leads for developing drugs that target diseases
caused by dysfunctional ion channels. At present this search is mostly carried out on a trial
and error basis, which is not very efficient. A better understanding of the toxin-channel
interactions would lead to a more rational design of drugs from toxins. In this project you will
study the binding of selected novel toxin peptides from plants to Kv1 voltage-gated potassium
channels using simulation methods such as molecular dynamics and docking. The aim of the
project is to find the key residues involved in the binding and study their mutations to see if a
mutant version can be developed which has a higher affinity for the Kv1.3 channel (target for
autoimmune diseases) but not for other Kv1 channels.
Honours Project Offering 2017 v1.1
17
Research Projects in Complex Systems
Research Projects in Complex Systems
Title of Project: The Role of Attention in Dynamics of Large-Scale Brain Activity
within a Corticothalamic Model
Supervisor: Tara Babaie
Co-supervisor: Professor Peter Robinson
Email Contact: [email protected]
Until recently, visual attention and awareness in primates were thought of as purely
cortical phenomena. Recent thought-provoking data, however, confirm some previous
neuroimaging demonstrations of attentional modulation in the primate thalamus, namely
lateral geniculate nucleus (LGN) and thalamic reticular nucleus (TRN). The vast majority
of visual information from the retina passes through thalamic relay cells in the LGN of the
thalamus then passing through the TRN before reaching visual cortex. Both
thalamocortical and corticothalamic neurons emit excitatory collaterals within the TRN
which suggests a possible modulatory role for the TRN in controlling thalamic activity. The
aim of this project is to improve theoretical models of thalamic sensory processing for
which we need to investigate the role of attention in terms of parameters and or structure
within the physiological representation of visual attention in whole model of brain. This
project at the core is involved with the identification of a theoretical model for attention,
including the associated neural parameters.
Title of Project: How does the brain compute? Distributed dynamical computation in
neural circuits
Supervisor: Dr Pulin Gong
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
One of the most fundamental problems about the brain is how it computes. To answer this
question, recently we have presented a concept of distributed dynamical computation
(DDC), in which computation or information processing is carried out by interacting,
propagating neural waves. The concept can merge dynamics and computation aspects of
the brain, which used to have great gaps between each other. The project will involve
making further links between dynamics and computation, including studying our current
models of spiking neural networks with synaptic dynamics to present novel solutions to
associative memory and visual feature binding in pattern recognition, and comparing the
distributed parallel computation capacities of DDC with those of conventional distributed
computation paradigms.
Honours Project Offering 2017 v1.1
18
Research Projects in Complex Systems
Title of Project: The physics of working memory in the brain
Supervisor: Dr Pulin Gong
Co-supervisor: Dr James Henderson
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Working memory, a core cognitive function, is responsible for the transient holding,
processing, and manipulation of information. Its neural correlate (persistent firing activity of
neurons), as shown in latest experimental studies, has great variability and is
topographically organized in the form of spatial gradients. These properties along with the
power-law forgetting behaviour of working memory can’t be explained by conventional
models with homogenous stable states. In this project, a new physical mechanism of
working memory, which is based on interacting, localized Turing-like patterns, will be
studied. Particularly, the collective subdiffusive dynamics emerging out from these
patterns will be used to account for the key dynamical properties and decoding accuracy
of working memory. For this project, students will also have a chance to analyse real
neural data recorded by multi-electrode arrays.
Title of Project: Turbulence in the brain: Detection of dynamic coherent structures in
collective neuronal activity
Supervisor: Dr Pulin Gong
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Cortical neural circuits are complex non-equilibrium systems whose collective dynamics
cannot be described solely in terms of oscillations or even low-dimensional aperiodic
(chaotic) dynamics. Very recently, we have developed a method that enables us to make
new discoveries regarding the collective dynamics of neural circuits; for instance, we have
found dynamic coherent structures such as vortices in the population activity of neurons.
This new finding therefore makes cortical spatiotemporal dynamics analogous to that in
turbulence fluids, in which a hierarchy of coherent structures are similarly embedded in
stochastic spatiotemporal processes.
This project will involve further developing this new method, analysing neural data
collected by our collaborators, and modelling the dynamic coherent structures by extending
the models developed by our group. The results of this project would further our
understanding of complex brain dynamics underlying flexible cognitive function.
Honours Project Offering 2017 v.1.1
19
Research Projects in Complex Systems
Title of Project: Googling the brain: Search of associative memory
Supervisor: Dr Pulin Gong
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Human memory has a vast capacity, storing all the knowledge, facts and experiences that
people accrue over a life time. Given this huge repository of data, retrieving any one piece
of information from memory is a challenging computational task. In fact, it is the same
problem faced internet search engines that need to efficiently organize information to
facilitate retrieval of those items relevant to a query. It is therefore of fundamental and
practical importance to understand what kind of dynamics and algorithms are used for
searching memory in the brain. Very recently, we have developed a biologically plausible
neural circuit model, which can quantitatively reproduce salient features of memory
retrieval. This project will involve further developing the model based on latest
experimental results and unravelling principled dynamics of memory search. These
principled dynamics will then be used to develop a novel searching algorithm applicable to
the huge repository of data as used by the Goggle search engine.
Title of Project: What determines the computational capacity of a brain?
Supervisor: Dr. Cliff Kerr
Co-supervisor: Dr. David Kedziora
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Our brains ultimately exist in order to make decisions, and the basis of this decisionmaking is the variety of computations that the brain is capable of performing. It is well
known that primate brains, consisting of tens of billions of neurons, can perform more
complex computations than, say, worms, who have a few hundred neurons. However,
surprisingly little is known about how computational capacity actually scales with network
size, neuron complexity, and other variables. This project will investigate quantitatively how
changes in a biologically realistic neuronal network model (including network size and the
complexity of the constituent neurons) affect the network’s computational capacity (as
measured by learning tasks and motor control of a virtual arm).
Title of Project: How aging affects information processing in the brain
Supervisor: Dr. Cliff Kerr
Co-supervisor: Dr. David Kedziora
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
All of us experience the process of aging -- the transition from a bumbling infant to a highly
capable Physics undergraduate and eventually to a bumbling pensioner -- yet we know
surprisingly little about how these obvious changes in behavior arise from structural and
functional changes in the brain. The first stage of this project is to quantify these changes
by applying data-mining methods to the world's largest database of healthy human
electroencephalographic (EEG) data. The second stage is to implement these changes in
a biophysically realistic spiking neuronal network model of the human brain. This will allow
the deficits in information processing at very young and very old ages to be explained
formally in terms of information theory.
Honours Project Offering 2017 v.1.1
20
Research Projects in Complex Systems
Title of Project: Dynamics of optogenetic stimulation in monkey cortex
Supervisor: Dr. Cliff Kerr
Co-supervisor: Dr. David Kedziora
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Optogenetics is a powerful procedure for performing precise perturbations to continuing
cortical dynamics in awake animals. However, current methods allow for only small
numbers of neurons to be recorded simultaneously. Using data from one of the world’s
leading primate optogenetics labs (via an international collaboration with Stanford
University), this project will explore how spiking neuronal network models can be used to
leverage these data into a more detailed understanding of the effects of optogenetic
stimulation. Specifically, this project will explore the limits of how neuronal dynamics can
be shaped via optogenetic stimulation, as well as the impact of this stimulation on
information flow and computation in the brain.
Title of Project: Developing marker-free motion tracking for magnetic resonance
imaging of the brain
Supervisor: Dr Andre Kyme (School of Physics), A/Prof Roger Fulton (Brain & Mind
Centre)
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Even slight movement of the head during MRI can dramatically degrade the usability of the
images. In this project you will develop a novel and highly accurate marker-free motion
tracking method to enable motion compensated MRI imaging. This would represent a
major advance for clinical brain imaging and basic neuroscience research.
It is very difficult for patients to remain completely still in a MRI scanner. Even small head
movements can have a huge impact on the quality of images obtained. This is especially
true for studies involving children and patients with dementia-related movement disorders.
Therefore, there is a strong push to develop motion compensation methods which rely on
accurately tracking head motion throughout a scan. Two key challenges make this very
difficult in MRI: (i) getting cameras to operate inside the high magnetic field, and (ii)
tracking within the highly restrictive bore geometry. Our collaborators at Stanford have
solved the first problem; now we want to develop a highly accurate marker-free motion
tracking method to estimate head movement from native features on the face in real-time.
This project will help you develop skills in computer vision, mathematical modeling,
experimental design and validation studies. It is an exciting opportunity to develop a new
and practical technology for state-of-the-art MRI imaging systems that could be
implemented in MRI scanners worldwide.
Honours Project Offering 2017 v.1.1
21
Research Projects in Complex Systems
Title of Project: Surface estimation of freely moving animals to enable quantitative
neuroimaging
Supervisor: Dr Andre Kyme (School of Physics), Prof Steven Meikle (Brain & Mind
Center)
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
We have developed the capability to image the brain of a rodent while it moves freely
inside a positron emission tomography (PET) scanner. This powerful technique has
enormous potential to improve our understanding of how brain function and behavior
relate to each other in mammals. The trajectory of gamma photons emitted from the
animal’s body and detected by our scanner during PET is relatively simple when the
animal is stationary; however, it is very complicated when the animal is allowed to move.
In order to properly account for this time-varying photon attenuation we need an accurate
model of the time-varying body shape. In this project you will investigate several novel
approaches to obtain this, including the Microsoft Kinect time-of-flight camera, structured
light, and machine learning methods.
This project will help you develop key skills in computer vision, mathematical modeling,
experimental design and validation studies.
Title of Project: Marker-free motion tracking for motion-compensated clinical brain
imaging
Supervisor: Dr Andre Kyme (School of Physics), A/Prof Roger Fulton (Brain & Mind
Centre)
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Even small movements of the human head during positron emission tomography (PET)
imaging can dramatically degrade the usability of brain images. In this project you will
develop and optimise a marker-free head motion tracking system and adapt it to a clinical
PET scanner to perform motion compensated brain imaging in real subjects.
It is very difficult for patients to remain completely still during long brain imaging studies
such as positron emission tomography (PET). Even small head movements can have a
huge impact on the quality of images obtained. This is especially true for studies involving
children and patients with dementia-related movement disorders. Therefore, methods to
measure and compensate for motion occurring during a PET scan are vital. The aims of
this project are to develop a highly practical marker-free method to estimate head motion
from native features on the face and to integrate this method into the workflow of a clinical
PET scanner.
This project will help you to develop key skills in computer vision, mathematical modeling,
experimental design and validation studies. It is also an excellent opportunity to gain
hands-on experience applying physics and engineering principles to solve real medical
problems in a hospital environment.
Honours Project Offering 2017 v.1.1
22
Research Projects in Complex Systems
Title of Project: Use of machine learning to accurately estimate rigid and non-rigid
body motion during imaging studies
Supervisor: Dr Andre Kyme (School of Physics), Dr Alistair McEwan (Biomedical
Engineering)
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Estimating the motion of freely moving animals during brain imaging studies is a highly
challenging but extremely important problem for neurological research. In this project you
will investigate and apply machine learning techniques to provide an innovative and
practical solution.
We have developed some key technologies that enable us to image the brain of a rodent
while it moves freely inside a positron emission tomography (PET) scanner. This powerful
technique has enormous potential to improve our understanding of how brain function and
behavior relate to each other in mammals. A vital component of this capability is the need
to accurately estimate the animal’s motion during a scan. Our current method relies on
optically tracking markers attached to the animal, but this is both impractical and errorprone. In this project you will investigate and test the feasibility of applying machine
learning methods to solve this problem without attached markers, and for very general
motion characteristics.
Machine learning is a booming field impacting a diverse range of applications from internet
searching to weather prediction to financial models. Skills in machine learning are highly
sought after by many employers. This project will help you to develop valuable knowledge
and experience in this area.
Title of Project: A purpose-built brain imaging scanner for awake, freely moving
animals
Supervisor: Dr Andre Kyme (School of Physics), Prof Steven Meikle (Brain & Mind
Centre)
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
We recently developed a technology that enables the brain of a small animal to be imaged
while the animal is free to move. This opens up a new class of experiments aimed at
relating mammalian brain function to behaviour. In this project you will develop, build and
validate a positron emission tomography scanner from the ground up, one that is
specifically designed and optimised for this application.
We have recently developed key technologies enabling us to image the brain of a rodent
while it moves freely inside a positron emission tomography (PET) scanner. This capability
allows powerful new experiments in which we can simultaneously study an animal’s
behaviour and measure what is happening in the brain. Up until now, we and others have
adapted the technique to existing commercial scanners. However, this brings inherent
limitations on imaging performance, motion tracking and animal motion. To overcome
these limitations, the aims of this project are to develop, build and validate a purpose-built
scanner for this important application. The project involves key physics, engineering,
computer vision and experimental design and validation challenges.
Honours Project Offering 2017 v.1.1
23
Research Projects in Complex Systems
Title of Project: Characterising and compensating for partial volume effects in
motion-compensated brain imaging of small animals
Supervisor: Dr Andre Kyme (School of Physics), Prof Steven Meikle (Brain & Mind
Centre)
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
We recently developed a technology that enables the brain of a small animal to be imaged
while the animal is free to move. This opens up a new class of experiments aimed at
relating mammalian brain function to behaviour. In this project you will develop, build and
validate a positron emission tomography scanner from the ground up, one that is
specifically designed and optimised for this application.
We have recently developed key technologies enabling us to image the brain of a rodent
while it moves freely inside a positron emission tomography (PET) scanner. This capability
allows powerful new experiments in which we can simultaneously study an animal’s
behaviour and measure what is happening in the brain. Up until now, we and others have
adapted the technique to existing commercial scanners. However, this brings inherent
limitations on imaging performance, motion tracking and animal motion. To overcome
these limitations, the aims of this project are to develop, build and validate a purpose-built
scanner for this important application. The project involves key physics, engineering,
computer vision and experimental design and validation challenges.
Title of Project: Development of an MR-compatible robot for fast and reproducible
manipulation of phantoms inside an MRI scanner
Supervisor: Dr Andre Kyme (School of Physics), Dr Alistair McEwan (Biomedical
Engineering)
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
In this project you will design, develop and validate a robot capable of fast and highly
reproducible manipulations of phantoms inside a magnetic resonance imaging (MRI)
scanner.
Compensating for head motion in magnetic resonance imaging (MRI) studies is extremely
important to avoid distortion and corruption of images. This is especially true for studies
involving children and patients with dementia-related movement disorders. Although many
motion compensation methods are being developed for MRI, there is currently no reliable
ground truth to validate and compare these methods. In this project you will design,
develop and validate an MR compatible robot capable of rapid and highly reproducible six
degree-of-freedom manipulation of MR phantoms inside an MRI scanner. This will provide
an excellent ground-truth system for assessing and comparing motion compensation
methods developed for MRI.
Honours Project Offering 2017 v.1.1
24
Research Projects in Complex Systems
Title of Project: Modeling of nonuniform brain waves using WKB methods and
Neural Field Theory
Supervisor: Dr James MacLaurin
Co-supervisor: Prof. Peter Robinson
Email Contact: [email protected] [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Many types of brain waves are found to be highly nonuniform and to have preferred
directions of propagation. These include 10 Hz alpha waves, which dominate during
relaxed waking states, particularly toward the back of the brain; 40 Hz gamma waves,
which are found to correlate with perception and to precede certain seizures that break out
from foci; 4 Hz theta waves, which are propagate through the hippocampus and are linked
with spatial navigation; and 1 Hz PGO waves that propagate from front to back of the brain
during deep sleep. However, there is as yet no clear set of theoretical predictions or
explanations of why this broad range of waves all exhibit similar non-uniform structure and
preferential propagation characteristics. Macroscopic brain activity can be predicted
Neural Field Theory, which yields a set of coupled partial differential equations for
resulting brain waves. This project involves the analysis of wave modes by approximating
the neural field equations using WKB expansion methods from quantum physics. This will
enable prediction and interpretation of mode structure and propagation characteristics, in
the various situations mentioned, which have wide application to brain phenomena and
disorders. The results will be tested against real brain data.
Title of Project: Real-world, scalable industrial nanotechnologies: from ideas to
start-up accelerators (multiple project opportunities)
Supervisor: Kostya (Ken) Ostrikov
Co-supervisor: Zhaojun Han, Michael Seo (CSIRO) and other colleagues
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Multiple project opportunities are available in the development of scalable, viable, and realworld industrial application-relevant, sustainable, environment-friendly and human healthbenign nanoscale technologies. The focused examples of specific applications (e.g.,
energy, water, food, health, environment, internet of things, etc.) and the most advanced
functional nanomaterials (e.g., graphenes, hybrids, etc.) will be used. This research relates
control of energy and matter at nanoscales (Grand Science Challenges) to practical
applications (Grand Societal Challenges). Specific roles of plasma-specifiuc effects that
lead to superior properties and performance of the nanomaterials in the applications will be
examined. The path toward the impact (from blue-sky ideas to spin-off accelerators and
commercial/investment-ready technology) will be explored, building for a career path in
industry, research and academy sectors. The precise mixture of experimental and
numerical components can be tailored to the student's wishes.
Honours Project Offering 2017 v.1.1
25
Research Projects in Complex Systems
Title of Project: Sustainable carbon lifecycles: from natural precursors to devices
and natural degradation
Supervisor: Prof Kostya (Ken) Ostrikov
Co-supervisor: Michael Seo (CSIRO) and other colleagues
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
There is a global demand in functional carbon-based nanomaterials and devices produced
from natural resources, as a future-oriented alternative to the commonly used purified
hydrocarbon sources. The major focus during this project period would be the fabrication of
the vertical ultrathin graphene architectures using a simple, cheap, highly-innovative and
more effective plasma-enabled alternative using natural resources, such as sugars, fats,
biomass, etc and their applications in gas and bio sensors, followed by natural degradation
which completes the sustainable carbon lifecycle. The precise mixture of experimental and
numerical components can be tailored to the student's wishes.
Title of Project: Printable graphene inks for roll-to-roll and 3D nanomanufacturing
Supervisor: Prof Kostya (Ken) Ostrikov
Co-supervisor: Adrian Murdock, Michael Seo, Zhaojun Han (CSIRO) and other
colleagues
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The outstanding properties of graphene sheets often disappear upon translation from
laboratory to industrial scale, in part because of their uncontrolled re-stacking. The
scalable production of high-quality graphenes and effective integration into functional
devices also remain to be explored [Science 347, 1246501 (2015)]. This project will
explore printing of graphene as a cost-effective and versatile deposition technique for
manufacturing graphene-based devices at large-area and high-volume. It is an important
step towards the commercialization of graphene-based technologies; yet the lack of stable
and well dispersed graphene inks at high concentrations is a major hurdle on the way to
printable graphene devices. This project will help developing printable graphene inks which
can be applied to the roll-to-roll and additive (3D) manufacturing of energy storage and
other devices. The precise mixture of experimental and numerical components can be
tailored to the student's wishes.
Title of Project: Individual differences in response to sleep deprivation and shiftwork
Supervisor: Svetlana Postnova
Co-supervisor: Peter Robinson
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
A number of interdisciplinary projects are available in the fields of alertness research and
prediction of individuals’ response to sleep deprivation and shiftwork. There is large
variability in changes of performance in response to sleep disturbances – some people
have significantly increased reaction times and rate of errors while others perform as good
as after a good night sleep. It is not yet known what mechanisms control this, but a number
of factors contribute, such as age, sex, and baseline performance level. In these projects
we will use biophysical model of alertness and experimental data from sleep laboratories
across Australia with the aim to identify potential mechanisms and model parameters
responsible for individual differences. This work is done under the framework of Alertness
CRC and involves collaboration with multiple universities and industry partners as well as
communication across experimental and theoretical fields.
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Research Projects in Complex Systems
Title of Project: Probabilistic modelling of the effect of sleep stage on sleep inertia
Supervisor: Svetlana Postnova
Co-supervisor: Peter Robinson
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Sleep inertia is a state of reduced alertness and performance in the first 0-4 hours after
awakening. Severity of sleep inertia depends on multiple factors, including the amount of
sleep debt and the sleep stage from which the person woke up. We have developed a
model of alertness that accounts for the effects of sleep debt on sleep inertia. In this
project this model will be extended to account for the sleep stage at awakening and
validated against experimental data. This work is done under the framework of Alertness
CRC and involves collaboration with multiple universities and industry partners as well as
communication across experimental and theoretical fields.
Title of Project: Phase resetting the biological clock to overcome jetalg
Supervisor: Svetlana Postnova
Co-supervisor: Peter Robinson
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Every day about 4 million people fly internationally. At their destination all these people
experience jetlag – a state of misalignment between the internal biological (circadian) clock
and environmental light-dark cycle. Usually it takes about 1 day to adjust to 1 h of time
difference, but for some people it takes significantly longer. During this time performance is
reduced and risk of accidents is increased. In this project we will apply analytical,
modelling, and numerical approaches to investigate methods for fast, so-called type 0,
resetting of the biological oscillator to a required phase. This would allow travellers to
significantly reduce duration of jetlag or, potentially, avoid it altogether, which is expected
to reduce sleepiness, improve wellbeing and reduce the number of fatigue-related
accidents.
Honours Project Offering 2017 v.1.1
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Research Projects in Complex Systems
Title of Project: Signature of heterogeneous time-delays in EEG spectra
Supervisor: Dr Paula Sanz-Leon
Co-supervisor: Prof Peter Robinson
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Time delays arise from finite propagation speed of singals along white matter pathways
and have been identified as on of the primary generation mechanisms of healthy brain
rythms.
Axonal lengths and conduction speeds are different across white matter pathways (the
brain’s wiring) So, there is a distribution of time delays connecting any two locations in the
brain (i.e., the time needed to get from A to B is not the same as that needed to get from A
to C). This project aims to deepen our current understanding of the signature of distributed
time delays across the cortex. To achieve this, we will run simulations of a family of
physiologically-based models that have been successfully applied to explain aspects of
different brain phenomena including sleep states and healthy wake brain rhythms. The
output of these simulations is equivalent to electroencephalography (EEG) recordings that
are commonly used as a diagnostic of brain function. The second part of the project
consists of frequency analysis of the simulated datasets to identify the signatures of
heterogenous time delays on the EEG power spectrum. Our group has already done
theoretical studies on this subject [1]. This project will build upon this work and will
incorporate nonlinear effects and spatial inhomogeneities. Finally, we will incorporate the
wiring information of real brains extracted from high quality datasets from the Human
Connectome Project (HCP) (this part depends on the progress of previous phases).
[1] Roberts and Robinson (2008) Modeling distributed axonal delays in mean-field brain
dynamics
Title of Project: Cellular automata on geodesic grids
Supervisor: Dr Paula Sanz-Leon
Co-supervisor: Prof Peter Robinson
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
This project will focus on studying the collective behaviour of simple units on geodesic
grids. These discrete dynamical units are known as cellular automata (CA). They have
been employed to simulate spatiotemporal features of brain dynamics and are typically
arranged on regular rectangular grids with periodic boundary conditions – equivalent to the
topology of a torus. However, in thir project we will use an alternative topology – the
sphere – and triangle cells. CA models are distinguished by their simple rules of local
interaction to compute complex global behaviour, which is often termed ‘emergent.’ Other
physics-based applications of CA include electric wave propagation, thermal modeling and
mechanics of carbon nanotubes. Finally, we will focus on modelling wave propagation on
arbitrary domains like the shape of a real brain (this part depends on the progress of
previous phases). The project involves a literature survey on CA and nonregular domains
and write part of the code to perform the simulations.
Honours Project Offering 2017 v.1.1
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Research Projects in Complex Systems
Title of Project: Cellular automata on geodesic grids
Supervisor: Dr Paula Sanz-Leon
Co-supervisor: Prof Peter Robinson
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
This project will focus on studying the collective behaviour of simple units on geodesic
grids. These discrete dynamical units are known as cellular automata (CA). They have
been employed to simulate spatiotemporal features of brain dynamics and are typically
arranged on regular rectangular grids with periodic boundary conditions – equivalent to the
topology of a torus. However, in thir project we will use an alternative topology – the
sphere – and triangle cells. CA models are distinguished by their simple rules of local
interaction to compute complex global behaviour, which is often termed ‘emergent.’ Other
physics-based applications of CA include electric wave propagation, thermal modeling and
mechanics of carbon nanotubes. Finally, we will focus on modelling wave propagation on
arbitrary domains like the shape of a real brain (this part depends on the progress of
previous phases). The project involves a literature survey on CA and nonregular domains
and write part of the code to perform the simulations.
Title of Project: Low-dimensional dynamics in cortical models and corticothalamic
model near instability
Supervisor: Dr. Dongping Yang
Co-supervisor: Prof. Peter A. Robinson
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
In many computational studies, cortical dynamics are operated in a linearly stable domain,
but the studies of human EEG show significant autocorrelation, which requires nonlinearities. The bifurcation in nonlinear dynamical systems can be indicated by statistical
properties such as increased autocorrelation length, increased variance, power law
scaling, and critical slowing down. However the reliability of these generic indicators
depends on the alignment in phase space between the input noise vector and center
eigenspace at the critical point. Therefore, it is important to understand the lowdimensional dynamics of cortical models near instability, and the sensitivities of each part
of the system. The project will be a good candidate for training student’s theoretical
analysis as well as computational abilities.
Honours Project Offering 2017 v.1.1
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Research Projects in Condensed Matter Physics
Research Projects in Condensed Matter Physics
Title of Project: Investigating spin-dependent conductance in transition-metal
porphyrin-graphene nanohybrids
Supervisor: Prof. C. Stampfl
Co-supervisor: Dr. C. Cui, S.A. Tawfik
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Metal porphyrins constitute a class of versatile molecules that play an important role in
diverse branches of science, such as biochemistry and materials science. For example,
metal porphyrins, metal phthalocyanines and related organic metal complexes have been
considered as light absorbers in solar cells, and porphyrin molecules perched between
electrodes made of metal clusters or graphene have been suggested in the context of
molecular electronics.
In the present project, the adsorption of transition metal porphyrins on defected graphene
and its consequences for electronic transport in these nanohybrids will be investigated by
means of density functional theory and quantum transport calculations. Properties of
interest are the stability, magnetic properties, spin dependence of conduction, and
whether the latter is (metal) element-specific.
The output of this project is expected to lead to a journal publication.
Title of Project: Optimization of the performance of low-dimensional nanostructures
using direct electric-field
Supervisor: Prof. C. Stampfl
Co-supervisor: Dr. C. Cui
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Nanotechnology is currently one of the leading scientific fields, intrinsically
multidisciplinary and holding the potential to lead to real-world breakthroughs in for
example the areas of nanoelectronics, clean energy, and green sustainable environment.
Two-dimensional, graphene-based structures are of high current interest due to their
unique properties and the ability to control and modify their atomic geometry and
consequently their physical and chemical properties.
This Honours project will investigate how and whether the performance of several such
nanostructures and quantum dots can be enhanced and controlled by using an electricfield. For example selective graphene oxide reduction (removing C atoms) and the
stabilising of graphone (a partially hydrogenated form of graphene that is ferromagnetic).
The studies will be carried out using first-principles quantum mechanical density-functional
theory calculations on supercomputer facilities.
The output of this project is expected to lead to a journal publication.
Honours Project Offering 2017 v1.1
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Research Projects in Condensed Matter Physics
Title of Project: Functionalisation of silica-alumina-based nano-catalysts for
production of biofuels and chemicals
Supervisor: Prof. C. Stampfl
Co-supervisor: Dr. C. Cui, A/Prof. J. Huang
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Improvement in the sustainability and productivity of the chemical industry is urgently
required to meet the increasing demand for fuels and chemicals and the impending
depletion of fossil-based resources. Presently, solid acid catalysts play and increasingly
important role not only in production of transportation fuels and petrochemicals, but also in
generating renewable fuels and chemicals from biomass. Silica-alumina-based catalysts
are most commonly used, whereby varying the Si/Al ratio in zeolite synthesis, the acidity
can be tuned. At present however, a detailed understanding of the atomic scale
mechanisms responsible for this is lacking. This project will address key questions
regarding the fundamental physics and chemistry of these novel solid acid nano-catalysts
with the overall goal of understanding and predicting their structure and reactivity. The
studies will be carried out using first-principles quantum mechanical density-functional
theory calculations on supercomputer facilities.
llThe output of this project is expected to lead to a journal publication.
Title of Project: Optimization of the performance of low-dimensional nanostructures
using direct electric-field
Supervisor: Prof. C. Stampfl
Co-supervisor: Dr. C. Cui
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Nanotechnology is currently one of the leading scientific fields, intrinsically
multidisciplinary and holding the potential to lead to real-world breakthroughs in for
example the areas of nanoelectronics, clean energy, and green sustainable environment.
Two-dimensional, graphene-based structures are of high current interest due to their
unique properties and the ability to control and modify their atomic geometry and
consequently their physical and chemical properties.
This Honours project will investigate how and whether the performance of several such
nanostructures and quantum dots can be enhanced and controlled by using an electricfield. For example selective graphene oxide reduction (removing C atoms) and the
stabilising of graphone (a partially hydrogenated form of graphene that is ferromagnetic).
The studies will be carried out using first-principles quantum mechanical density-functional
theory calculations on supercomputer facilities.
The output of this project is expected to lead to a journal publication.
Honours Project Offering 2017 v.1.1
31
Research Projects in Condensed Matter Physics
Title of Project: Atomic-scale Characterisation of Semiconductor Nanowires
Supervisor: Rongkun Zheng
Co-supervisor: Simon Ringer
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Semiconductor nanowire heterostructures are promising for nanoelectronic, nanophotonic
and nanooptoelectronic devices due to their superior electrical and optical properties
compared with other materials. Precise control over the composition and perfection of
interfaces is required for the successful fabrication of high-performance devices. This
project aims to understand the origin and nature of variations in composition and
interfaces and to thereby improve the quality of nanowire heterostructures. By developing
growth-structure-property relationships, we will be positioned to grow high-quality
nanowire heterostructures suitable for various devices.
Title of Project: Graphene: a journey of appreciation and exploration via
computational simulations
Supervisor: Rongkun Zheng
Co-supervisor: Carl Cui
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Graphene, single atomic layer of graphite, exhibits truly spectacular structural,
mechanical, electronic, thermal and possibly magnetic properties. Graphene and its
derivatives hold promise for a vast range of nanotechnologies, particularly in the emerging
field of graphene-based nanoelectronics and nanospintronics. This project aims to study
several key graphene-based nanostructures including nanoribbon, nanodots and
nanoantidots. Their optical, electrical and magnetic properties will be investigated by the
state-of-the-art first principles (no experimental parameters) simulations. The output of this
Honour project is expected to result in 2 international journal publications.
Title of Project: Development of high performance NdFeB permanent magnets
Supervisor: Rongkun Zheng
Co-supervisor: Martin Xu
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
NdFeB-based permanent magnets have been widely used in many industries such as
communication, electronics, information and transportation. Comprehensive investigations
are needed on their processing conditions, microstructure as well as magnetic properties.
This project, in collaboration with industry partners, will clarify processing-structureproperty relationships in NdFeB permanent magnets and optimise the microstructure
control for better performance.
Honours Project Offering 2017 v.1.1
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Research Projects in Particle Physics
Research Projects in Particle Physics
Experimental Physics
Title of Project: Simultaneous measurements of Standard Model cross-sections at
the Large Hadron Collider
Supervisor: Prof. Kevin Varvell
Co-supervisors: Dr Kevin Finelli, Dr Jin Wang
Email Contact: [email protected], [email protected],
[email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Large Hadron Collider is designed to produce exotic particles such as the Higgs
boson, top quark, and W and Z bosons by colliding protons together and using gigantic
detectors like ATLAS to examine the debris. By fitting data collected by ATLAS to
predictions made by the Standard Model, the model which describes all fundamental
interactions of elementary particles, we can simultaneously study the production
mechanisms of several rare processes. This simultaneous measurement allows us to
perform a global test of the Standard Model which has the potential to reveal new physical
processes beyond the Standard Model, and will attempt to resolve or confirm
discrepancies seen in other LHC measurements.
The student will have the opportunity to collaborate with scientists based at CERN and will
be involved in statistical analysis of LHC data. This work would be suitable both for
standalone honours projects and for projects leading into subsequent PhD research.
Title of Project: Data acquisition for an upgraded ATLAS detector at a High
Luminosity Large Hadron Collider
Supervisor: Prof. Kevin Varvell
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
In the future the Large Hadron Collider at CERN will be upgraded to high luminosity
running (the so-called HL-LHC) and this will require the giant detectors such as ATLAS to
undergo their own upgrades in order to be able to collect data at significantly higher rates.
Planning for this is already underway, and in this project a local test-stand for studying fast
read-out possibilities for the new ATLAS inner tracker (ITK) will be developed.
Honours Project Offering 2017 v1.1
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Research Projects in Particle Physics
Title of Project: Higgs property measurement with ATLAS experiment at the Large
Hadron Collider
Supervisor: Prof. Kevin Varvell
Co-supervisor: Dr Jin Wang
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The discovery of the Higgs resonance in 2012 at CERN’s Large Hadron Collider (LHC) is
definitely a milestone in particle physics. It led to the attribution of the 2013 Nobel Prize in
Physics awarded jointly to François Englert and Peter Higgs. There were immediately
decisive questions to be answered: such as whether all the properties of the discovered
particle are compatible with the prediction of the Standard Model (SM) of particle physics,
as any deviations observed would call for the physics beyond the SM (BSM). One priority
is to check how the Higgs interacts with other SM particles and to measure the
corresponding Higgs couplings. Another priority is to verify that the new particle's own
intrinsic spin has the SM value of 0. There have been great efforts on measuring Higgs
properties since LHC Run 1 (2009-2013) and the current results are still limited by
statistics.
This project will study Higgs boson coupling and test different Higgs spin hypotheses
through the vector boson fusion production (VBF) of the Higgs in the channel where the
Higgs decays to two photons. The measurement will use the data collected by ATLAS
experiment in LHC Run 2, which started in 2015 with proton-proton collision at centre-ofmass energy of 13 TeV (Run 1 has provided 7 and 8 TeV collisions). The excellent
performance of the LHC will result in huge amounts of collected data by the end of 2016. It
will enable us to probe the SM further and to possibly find clues about the physics that lies
beyond it.
Title of Project: Testing the Standard Model through precision measurement Precision Higgs measurements
Supervisor: Dr Anthony Morley
Co-supervisor: Prof. Kevin Varvell
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Higgs Boson discovery, while interesting and extremely exciting, was very much
expected physics.
The ATLAS detector has, so far, found no traces of truly new physics: supersymmetric
particles, extra dimensions, etc. At present there is no strong evidence for any of the new
models and at the same time a large number of these models cannot be ruled out.
Studying the newly discovered Higgs Boson in great detail is one potential avenue to
finding new physics. In this project we will study ways to enhance the ability of the ATLAS
detector to measure the properties of the Higgs boson.
Honours Project Offering 2017 v.1.1
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Research Projects in Particle Physics
Title of Project: Design and optimisation of the next generation tracking algorithms
for the LHC
Supervisor: Dr Anthony Morley
Co-supervisor: Prof. Kevin Varvell
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Large Hadron Collider (LHC) at CERN has turned on again is running at 13TeV. In
order to expedite the search for new phenomena, the LHC will endeavour to
simultaneously collide more protons than it has ever done before. All of these
simultaneous collisions introduce a number of experimental challenges when trying to
identify what has occurred in each of these collisions. This project will address one these
challenges, specifically the accuracy and speed with which we reconstruct charged
particles in these collisions. The project will expose the student to machine learning,
optimisation and pattern recognition techniques. The work will contribute to the design of
the planned upgrades to the ATLAS tracking detector, which will be replaced in 2022.
Title of Project: Particle composition from high energy particle hadronic
interactions
Supervisor: Dr Anthony Morley
Co-supervisor: Prof. Kevin Varvell
Email Contact: : [email protected] , [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Detailed computer based simulations of high-energy particle collisions are a vital tool for all
measurements performed at accelerators like the Large Hadron Collider (LHC). The
simulation of high energy particles interacting with detector matter are restricted by the
limited data available to tune the simulation. In particular, limited data are available on the
species and kinematics of secondary particles produced in hadronic interactions. The
ATLAS detector is able to reconstruct hadronic interaction vertices with sufficient precision
that the target material (silicon, beryllium, carbon, aluminium) can be identified, and with
the use of information about the energy deposit of secondary hadrons in subsequent layers
of the inner detector (dE/dX), the secondary particle species can be identified (pions can
be separated from protons and kaons). The goal of this project is to study kinematic
distributions of secondary hadrons from interactions in specific layers of the inner detector
and to provide kinematic distributions and species distributions that assist in the tuning of
the numerical models used to simulate these interactions.
Honours Project Offering 2017 v.1.1
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Research Projects in Particle Physics
Title of Project: Searching for exotic mesons at ATLAS in final states including
neutral particles
Supervisor: Dr Bruce Yabsley
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Many so-called exotic mesons have been seen since 2003: particles that do not have the
quark-antiquark structure of the established mesons such as the pions, kaons, D-mesons,
etc. The first, and still one of the most interesting states, is the X(3872). One model of its
structure is that it is _two_ mesons, a D0 and a D*0bar, weakly bound by pion exchange
(like a proton and a neutron forming a deuteron). Many have speculated that there should
be a related state, an "Xb", made of B0 and B*0bar mesons.
The search for an Xb in LHC Run 1 data (from the ATLAS experiment) was performed here
in Sydney, using a fully charged final state. To fully exploit the large Run 2 dataset, it may
be necessary to extend the search to final states that include neutral particles: gammas
and neutral pions. Such states are more difficult to reconstruct, but also provide a rich set
of observables that can be used to suppress background processes. In this project, you
will help to study and design such a search. There may be potential for this work to lead to
a future postgraduate project.
Title of Project: Measuring exotic meson line shapes with multidimensional fitting at
Belle II
Supervisor: Dr Bruce Yabsley
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The 2003 discovery of the X(3872), a charmonium-like particle which does not have the
normal quark-antiquark structure of the classic mesons, has led to a revolution in meson
spectroscopy. But the structure of the X(3872) itself is still imperfectly known. A highresolution measurement of the lineshape of certain X(3872) decays would be decisive, but
no current experiment has the required precision.
An X(3872) analysis at the Belle experiment in 2011 found that the use of multidimensional
fits to the data could resolve decay widths narrower than the nominal resolution of the
detector. This intriguing result has not been further studied, but could be important for the
measurement of decay widths and lineshapes at the successor experiment, Belle II. In this
project, you will investigate and understand this effect, and assess its potential for
measurements at Belle II.
Honours Project Offering 2017 v.1.1
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Research Projects in Particle Physics
Theoretical Physics
Title of Project: Gravitational waves from the electroweak phase transition
Supervisor: Dr Archil Kobakhidze
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
According to the standard hot Big Bang scenario, the early universe was in the state of hot
plasma comprising all known elementary particles. At high temperatures the ground state
of the system of elementary particles, which is defined by the Higgs field configuration, was
symmetric under the electroweak gauge transformations and hence all particles were
massless. As the universe expands it cools down and eventually undergoes a phase
transition from the electroweak-symmetric to the electroweak-broken phase, where particle
mass generation occurs and the universe as we know it starts to form.
In this project we investigate the nature of the electroweak phase transition within
theoretical models with an extended Higgs sector. Namely, we will be looking the cases
when the phase transition occurs through bubble nucleation (1st order phase transition).
The bubbles of asymmetric phase generate gravitational waves, which can be observed at
space-based observatories such as eLISA and others.
Title of Project: Hunting for dark matter at the LHC within unitarised effective field
theories
Supervisor: Dr Archil Kobakhidze
Co-supervisor: Dr Michael Schmidt
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The experimental search for dark matter particles is one of the main scientific priorities of
the physics program at the Large Hadron Collider (LHC). Effective field theory (EFT) is the
most convenient theoretical framework for model-independent interpretation of the
experimental data on dark matter. However, its direct application to experiments at high
energies is plagued with serious theoretical problems, such as violation of perturbative
unitarity. Hence, the use of EFT for interpreting the LHC data is limited.
Recently we have suggested a new framework of unitarised EFT, which is free of the
above-mentioned theoretical inconsistencies. The aim of this project is to expand the
unitarised EFT formalism and apply it to the analysis of the latest dark matter data from the
LHC.
Honours Project Offering 2017 v.1.1
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Research Projects in Particle Physics
Combined Theoretical and Experimental Particle Physics
Title of Project: Nonlocal CPT violation in neutral meson systems
Supervisors: Dr Archil Kobakhidze and Dr Bruce Yabsley
Co-supervisor:
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Standard Model of particle physics is CPT-symmetric: processes related by charge
conjugation (C), parity (P), and time reversal (T) should behave identically. (One
consequence is the identical masses of the proton and anti-proton.) There are strong
theoretical arguments that the CPT symmetry should hold, but various proposals for “new
physics” at high energies can produce CPT violation. The experimental effects can be
striking, including vacuum birefringence and other violations of Lorentz symmetry.
There is a recent theoretical proposal that nonlocal effects could produce CPT violation
while preserving Lorentz covariance. The experimental implications of this have been
studied for neutrinos, but not for other physical systems. In this project, you will study the
CPT symmetry within the framework of quantum field theory, learn the rich set of
experimental results on the mixing of neutral mesons (such as the K0, B0, and their
antiparticles), and determine the implications of nonlocal CPT violation for neutral mesons.
Honours Project Offering 2017 v.1.1
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Research Projects in Photonics and Optical Science
Research Projects in Photonics and Optical Science
Title of Project: Compact THz devices using topologically protected transport in
metawaveguides
Supervisors: Dr Shaghik Atakaramians, Dr Andrea Blanco Redondo
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Imaging and sensing with electromagnetic radiation in the terahertz (THz) frequency
regime have already found applications in science and industry, such as security and
safety screening, and process monitoring. The frequency range also lends an enormous
bandwidth and thus a large link capacity for high-speed short-range communications. Lack
of compact and flexible THz components hinders the integration and hampers the broadscale market introduction of THz systems. On the other hand, topological photonics is a
bursting new field in which certain global properties of the wave vector space of the
photonic structure are harnessed to create novel phases of light that can be immune to
reflections. In this project we aim to use novel concepts from topological photonics to
create metawaveguides capable of transporting THz radiation around sharp corners
without any reflection. A periodic array of metallic cylinders (simple photonic structure)
attached to metallic plates behaves as a photonic topological insulator permitting
reflectionless transmission at sharp corners leading to compactness of THz devices. The
project involves design and numerical modelling of a topological metawaveguide,
fabrication and THz characterization.
Title of Project: Exploiting nanofibres to tailor transmission and phase front of
metasurfaces
Supervisors: Dr Shaghik Atakaramians
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Recently we introduce a new platform to achieve a strong magnetic response in optical
fibres. We have shown that a coupled dipole-fibre system, an electric dipole placed near
an optical nanofibre, can produce strong magnetic response. We have demonstrated that
in such a system the electric response is suppressed and the magnetic resonance is
enhanced in such a way that the energy in the magnetic mode can be made two orders of
magnitude higher than that of the electric mode of the system. In this project we aim to
harness the optical nanofibre to tailor the transmission and phase front through
metasurfaces consisting of array of electric and/or magnetic dipoles. The metasurfaces
are a platform to design flat optical components including planar lenses, optical vortex
plates, holograms and waveplates. This collaborative project (USyd, ANU and UniSA)
involves design, numerical modeling and experimental demonstration in Terahertz
frequency range.
Honours Project Offering 2017 v1.1
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Research Projects in Photonics and Optical Science
Title of Project: Multi-channel sources of correlated photons in silicon
Supervisor: Dr. Bryn Bell and Prof. Benjamin J. Eggleton
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Quantum communication aims to exploit the quantum properties of light to provide,
amongst other things, totally secure encryption for information transmitted over optical
fibre. A key component for quantum communication is a source of correlated or entangled
photons, which can then be distributed between widely separated users. This project will
be to experimentally test sources based on silicon photonic chips, which can generate
correlated photons across a large range of wavelengths, and incorporate filters elements to
divide them into different wavelength channels. The aim is to demonstrate that a single
silicon chip can provide correlated photons between several pairs of users to communicate
securely over a network, by using wavelength division. In this project you will gain
experience in quantum photonics experiments, working with photonic chips, and single
photon measurements.
Title of Project: Optimization of a silicon ring resonator as a quantum light source
Supervisor: Dr. Bryn Bell, Dr. Alvaro Casas-Bedoya, and Prof. Benjamin J. Eggleton
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
A key component for optical quantum computing and quantum communication is a source
of correlated or entangled photons, and silicon ring resonators are a promising design for
this. These are optical cavities on a silicon chip, where light is guided round a closed loop
many times, leading to a large enhancement in the optical nonlinearity. This nonlinearity
can generate correlated photons in a compact, efficient source. However theoretical work
has pointed out that there is a trade-off involved: circulating for longer in the ring resonator
enhances not only the nonlinearity, but also the photon losses. This experimental project
will use a sophisticated opto-electronic chip that contains integrated heaters to adjust a
ring resonators’ properties, and study how increasing nonlinear enhancement affects the
detected rate of correlated photons, the signal to noise ratio, and the photons’ spectrum.
You will gain experience in quantum photonics, working with photonic chips, and single
photon measurements.
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Research Projects in Photonics and Optical Science
Title of Project: Experimental demonstration of novel soliton in photonic crystal
fibre
Supervisor: Dr. Andrea Blanco-Redondo
Co-supervisor: Prof. Martijn de Sterke
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
This experimental project aims at demonstrating the existence of a new class of nonlinear
solitary wave, the pure-quartic soliton, in optical fibers for the first time.
Our recent experimental discovery of pure-quartic solitons occurred in a slow-light photonic
crystal silicon chip. Demonstrating this phenomenon in optical fibers is of the utmost
importance since it will prove that pure-quartic solitons are a general phenomenon and it
will enable the subsequent development of game-changing applications such as the purequartic soliton fibre laser, which has the potential to overcome the limitations of current
soliton fibre lasers. We are currently working on the design of a photonic crystal fibre
appropriate for such demonstration.
The student undertaking this project will work on the fabrication of the photonic crystal fibre
and will use the advanced ultrafast optics characterization techniques available in our lab.
Title of Project: Hypersound signal processing
Supervisor: Dr. Amol Choudhary, Dr. David Marpaung and Dr. Mark Pelusi
Co-supervisor: Prof. Benjamin Eggleton
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The future of high-capacity communications is based on photonic circuits. We are
investigating fundamental physical phenomena for applications in communications. Our
group has pioneered digital integrated signal processing with several breakthrough results.
Our recent breakthrough explored the interaction of light and sound to achieve worldrecord performance. Typically, this interaction known as stimulated Brillouin scattering is
widely regarded as being detrimental in telecommunications. We have now revolutionized
this perspective with our recent results
(http://sydney.edu.au/news/physics/1737.html?newsstoryid=15955).
We are also pioneers of integrated analog signal processing based on light-sound
interaction, with several state-of-the-art results. However, a deeper understanding of the
dynamics of this interaction is required. The evolution of noise and linearity are key
elements before such devices can be deployed in the field.
In this project, the student will explore light-sound based analog and digital systems and
will model the evolution of noise in this exotic process. A successful completion will give
the scientific community a deeper understanding of this process and will also demonstrate
exquisite signal processing functionalities on a photonic chip.
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Research Projects in Photonics and Optical Science
Title of Project: Vibrations in silicon
Supervisor: Dr. Alvaro Casas Bedoya and Dr. Amol Choudhary
Co-supervisor: Prof. Benjamin Eggleton
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Strong light beams can literally shake the material at the nanoscale. These vibrations
result in hypersound which can be harnessed for several exotic applications on a photonic
circuit. Silicon is the most widely used electronic platform and was the basis of the
electronics revolution of the 20th century. A multi-trillion dollar industry is based on this
material and we are moving towards the next revolution: a photonic-phononic revolution! In
this project we will explore the development of optical and phononic circuits in silicon.
There will be opportunities to model and design photonic-phononic circuits in this project.
The state-of-the art cleanrooms at the Sydney nanoscience hub will allow the student to
fabricate their own devices and test them in our labs at CUDOS. At the end of the project,
the first ever circuit with both photonic and phononic components will be demonstrated.
This will be a crucial step towards the long-term vision of integrating photonic-phononic
circuits with electronics on a single chip.
Title of Project: Build your own compact phonon-driven laser
Supervisor: Dr. Amol Choudhary
Co-supervisor: Prof. Benjamin Eggleton
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The first ever laser consisted of a flash-lamp-pumped ruby rod and was built by
T.H.Maiman in 1960 and since then lasers have captured the imagination of many
physicists and the general public alike. Lasers with a narrow linewidth can have
applications in coherent optical telecommunications, microwave photonics and
spectroscopy. This project aims to exploit one of the strongest non-linearities known to us:
stimulated Brillouin scattering (SBS) to develop compact narrow-linewidth lasers which can
fit on the palm of the hand. Simulations will be initially carried out, after which, using
CUDOS’ expertise in integrated optics and SBS, an on-chip Brillouin laser will be
developed with a high performance for operation at the telecom wavelengths. This will be
followed by the realisation of a laser in the ‘eye-safe’ region at a wavelength of 2000 nm.
Such lasers can have important applications in atmospheric sensing of water, ammonia
and carbon dioxide.
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Research Projects in Photonics and Optical Science
Title of Project: Unleashing the power of a new solitary wave
Supervisor: Prof. Martijn de Sterke
Co-supervisor: Dr. Andrea Blanco-Redondo
Email Contact: [email protected], [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Optical solitons are solitary optical waves that propagate unperturbed, in a particle-like
fashion. They originate from the interplay of linear and nonlinear effects that
counterbalance each other to produce self-reinforced localized waves. Thanks to this
robustness they have played a major role in breakthrough applications such as frequency
combs and supercontinuum generation facilitating far-reaching advances in medical
applications, metrology and even in the understanding of rogue waves in the ocean.
However, conventional optical solitons have inherent limitations in crucial technologies
such as ultrafast lasers used for surgery of human tissue amongst other important
applications. We recently discovered an entirely new class of optical soliton, which we
termed pure-quartic soliton, with features that suggest an excellent potential for producing
transformational advances in ultrafast lasers.
This project aim is advancing towards the development of pure-quartic soliton lasers and
can comprise analysis, simulations and/or experiments, depending on the preferences and
the skills of the student.
Title of Project: Improved detectors for PET
Supervisor: Prof. Martijn de Sterke
Co-supervisor: Prof. Steve Meikle (medical physics)
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Positron emission tomography (PET) is an imaging technique that enables 3D images of
the biodistribution and kinetics of radio-labelled molecules to be recorded in living
subjects. PET relies on the detection of 511 keV gamma rays which are converted to
visible light (λ≈430 nm) in thin dense crystals and converted to an electrical signal by a
photodetector. PET detector performance is determined by the dimensions of the crystals
and the intensity and time distribution of the collected light. However, making the crystals
too long and thin increases the likelihood of light trapping, while making them shorter
degrades the gamma ray absorption efficiency. The aim of this project is to explore the
potential of thin optical gratings (“photonic crystals”) applied to the crystal surface to
enhance light collection from thin, dense scintillators. This interdisciplinary project you will
design an appropriate structure using existing software and perform Monte Carlo
modelling to investigate the effect of grating parameters on light trapping and detector
performance.
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Research Projects in Photonics and Optical Science
Title of Project: Slow light for enhanced nonlinear effects
Supervisor: Martijn de Sterke
Co-supervisor: Boris Kuhlmey
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Light in vacuum travels at, well, the speed of light c. In a medium it is slowed down by a
factor given by the refractive index n. Slow light refers to light that goes even slower than
this, which can be achieved by structuring the medium. For example, periodic refractive
index jumps can cause multiple reflections, leading to effective speeds much smaller than
c/n. Not only is slow light really neat, it also is useful: nonlinear optical effects like
frequency conversion and soliton formation, are normally weak, but are enhanced when
the light travels slowly. In this project you will investigate how slowly light can go in media
with properties that do not vary longitudinally, but are otherwise arbitrary. Such media are
relatively easy to fabricate, for example in a fibre draw tower (of which the School has
one). In this project you will use cutting-edge computational tools and techniques to
investigate to what degree light can be slowed down in such media, and to calculate the
resulting enhancement of nonlinear effects.
Title of Project: Graphene oxide sub-wavelength optical elements for optical
instrumentation
Supervisor: Martijn De Sterke
Co-supervisor: Sergio Leon-Saval
Email Contact: [email protected] [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Astronomers are just starting to embrace photonics as one of the most promising venues
for the next generation of astronomical instruments. The reason for doing so is that while
the size of telescopes keeps increasing, it is impractical for the optical instrumentation
required to analyse the light, to grow with it. While in photonics, research in nanophotonic
elements and components is a flourishing area, this research project will explore the
exciting possibility to introduce nanoscale optical elements in astronomical instrumentation
for the very first time. This project will explore, initially through modelling, and
subsequently experimentally, graphene oxide sub-wavelength structures with nanoscale
dimensions to produce a variety of optical elements such as nano-composite lenses and
dispersive element which are suited to be attached to the end of an optical fibre.
Title of Project: A novel way to characterize ultra-short optical pulses
Supervisor: Martijn De Sterke
Co-supervisor: Clark Li
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The characterization of ultra-short optical pulses (tens of femtoseconds) is an important
problem and which is a challenge because even the fastest optical detectors responses
times of at least a few picoseconds. Typically, therefore, such pulses are measured by
mixing one such pulse with a time-delayed version of itself in an interferometer, and then
measuring the resulting signal as the delay is varied. A completely different way of
characterizing such pulses is to measure how these pulses depend on position, for
example by letting them propagate parallel to a weak grating. This grating can be included
in the laser cavity in which the pulse is generated, and would diffract a small amount of
energy into one of the diffracted orders. This spectrally resolved information can then be
analysed. This is a theoretical project that will establish whether or not an approach of this
type may be fruitful for pulse characterization.
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Research Projects in Photonics and Optical Science
Title of Project: Hybrid Plasmonic Sensor for Lab-On-Chip Applications
Supervisor: Dr Stefano Palomba
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The demand for more effective, customized therapies, real-time monitoring and early
disease diagnostics in medicine, biology and environmental science have as a common
need the capability of detecting low concentrations of the active molecules of interest in
real time, with portable, cost-effective and reliable devices. Although fluorescence has
been so far the preferred platform, the information that it supplies is limited and issues like
quenching and photobleaching compromise the effectiveness of the technique. On the
contrary, Raman spectroscopy can not only detect single molecule but also the unique
chemical signature of each specific molecule. But the Raman signal is extremely weak.
However the Raman signal drastically augments when the molecules are located in close
proximity with metallic nanostructures or in an intense optical field. The usage of the
former requires a preliminary preparation of the sample and has the molecule to be
detected bound to the gold nanostructures, which is not compatible with cost-effective, fast
and integrated sensors. One solution could resides in the design and engineering of a
nanofocusing device which can generate enough high field intensity in a specific area to
induce enough Raman scattering signal, generated by the passage of the molecule of
interest in the nanospot. This could become the preferred platform for Lab-On-Chip (LOC)
devices.
Proposed work: This project requires a thorough literature review on nanofocusing devices
and a subsequent design of a nanofocusing system which could be integrated in a
nanofluidic system for Raman excitation and detection. This first part could be followed by
the fabrication and preliminary test of the modelled device for a proof of principle
measurement. This work will pave the path to the development of an on-chip plasmonic
sensor prototype for LOC applications.
Title of Project: Hybrid Plasmonic-dielectric resonator investigations
Supervisor: Dr Stefano Palomba
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Optical µ-resonators with high quality factor promise to be one of the most sensitive
biosensor for Lab-On-Chip devices. µ-resonators are mainly fabricated in silica by melting
a fibre optic end or in Silicon by nanolithography techniques. Transparent materials like
glasses or semiconductors (photonics) exhibit very low optical losses, but cannot generate
very high field enhancements; opaque, absorbing materials like metals (plasmonics) can
enormously compress light, giving rise to huge light intensities, however the high losses
tend to prevent this approach from reaching its full potential. An alternative approach
resides in exploring the best characteristics of metals and dielectrics into a hybrid
structure, which exhibits high light intensities, moderate losses and on-chip compatibility.
We have designed a procedure to theoretically model and extract the geometrical
characteristics of a dielectric resonator coupled to a plasmonic antenna and incoupling/out-coupling ports.
Proposed work: In this project you will use this theoretical tool to design a dielectric
resonator coupled to a plasmonic antenna for enhanced light-matter interactions. Once
the design is completed, we will fabricate the systems and experimentally test their
performance.This work will potentially lead to high quality publications.
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Research Projects in Photonics and Optical Science
Title of Project: Gap Plasmon for Enhancing SiC Quantum Dots Single Photon
Emission
Supervisor: Dr Stefano Palomba
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Information processing and data exchange is fundamental to our society increasing the
demands for more computational power, more secure communication protocols, less
power consumption and small chip footprints. Quantum optics promises to fulfil all these
needs and even more, bringing our computing and information processing to a level today
unimaginable.
One of the most promising scheme for quantum computation on chip requires the
generation of single photons. Therefore an on chip single photon source operating at room
temperature is a key requirement for future quantum information technologies, such as
quantum computing, quantum key distribution, and quantum processing. To date, efficient
generation of single photons is still under investigation, since no specific platform has
prevailed. Currently the majority of the single photon sources are obtained by defect
inclusions in diamond nanocrystals, or accurate growth of quantum dots, or utilizing
multiplexing techniques. A very promising new material is SiC, an important wide-bandgap
semiconductor with outstanding electrical, thermal, mechanical and biocompatible
properties, and more in details SiC tetrapods.
Proposed work: In this project you will experimentally study the optical emission properties
of SiC tetrapods coupled to a gap plasmon in the contest of the generation of single
photons. This project will generate the building blocks to develop an efficient platform for
single photon generation on-chip for future integrated quantum technologies. This work
will potentially lead to high quality publications.
Title of Project: Localized Graphene Doping for Generating Visible Surface Plasmon
Polaritons
Supervisor: Dr Stefano Palomba
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
In recent years the atomic thick carbon sheet, called graphene, has showed outstanding
electrical, mechanical and optical properties. Many of these properties are a consequence
of the linear and continuous density of states distribution. Coherent electron oscillations,
called Surface Plasmon Polaritons (SPPs), can be launch at the interface between
graphene and a dielectric. SPPs maintain the same frequency of the incident optical field
which generated them but different wavelength, hence generating light compression and
propagation at the nanoscale, well beyond the diffraction limit. It has been recently
suggested that SPPs can be launched in the visible part of the spectrum and tuned as a
function of the local doping level of the graphene sheet. This doping can be performed by
injecting electrons and therefore changing the local Fermi level.
Proposed work: In this project you will experimentally study the SPPs generated by
electrically doping a graphene sheet with a localized electrode, validating the theoretical
predictions. This work will potentially lead to high quality publications.
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Research Projects in Photonics and Optical Science
Title of Project: Miniaturized Photonic Chip, Optical Signal RF Spectrum Analyser
Supervisor: Mark Pelusi
Co-supervisor: Alvaro Casas Bedoya, Ben Eggleton
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The RF spectrum is a powerful diagnostic tool for characterizing the fast, time varying
waveforms of signals. Its measurement has been shown possible in the optical domain by
propagation through a waveguide, where the signal mixes nonlinearly with another
propagating field at different frequency, to create the RF spectrum that is measurable by
standard optical spectrum analysis. This approach has the advantage of enabling an ultrawide measurement bandwidth (beyond 1 Terahertz) that far exceeds the capability of state
of the art, high speed opto-electronics. This project will investigate the world’s first, fully
integrated chip “all-optical” RF spectrum analyser, based on an in-house designed,
photonic integrated circuit that has recently been fabricated in silicon, and aim to
demonstrate its capability for broadband RF spectrum analysis of high speed optical
signals.
Title of Project: Broadband Optical Frequency Combs for High Speed Internet
Supervisor: Mark Pelusi
Co-supervisor: Ben Eggleton
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Optical frequency combs have wide-ranging applications in astronomy, meteorology, and
medical imaging to bio-sensing, and more recently, for optical communications, by
enabling a single laser source to carry hundreds of data channels on different frequencies,
in place of the hundreds of single frequency laser modules used in today's multi-Terabit/s
systems. This can enable more energy efficient, higher speed internet. This project will
investigate generating low noise, broadband optical frequency combs for carrying higher
bit rate signals, and aim towards a laboratory demonstration of a laser source capable of
carrying over one hundred times more information capacity than a conventional single
frequency laser.
Title of Project: Overcoming the Optical Nonlinear Shannon Limit for High-Speed
Communications
Supervisor: Mark Pelusi
Co-supervisor: Ben Eggleton
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Nonlinear Shannon Limit is a fundamental bottleneck to the growth of the internet,
and originates from the Kerr effect in optical fibre inducing a refractive index change in
proportion to the light intensity propagating through it. The fast effect, responding on a
femtosecond time-scale, is complicated by optical intensity noise and the fibre’s chromatic
dispersion, making its full compensation in real communication systems near impossible.
This project will explore novel optical signal processing techniques that can manipulate the
phase of data carrying photons to better suppress the induced signal distortion, and aim
towards a laboratory demonstration of the device enabling record-breaking long distance
transmission of high bit rate optical signals in optical fibre.
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Research Projects in Photonics and Optical Science
Title of Project: Hybrid Plasmonic Waveguide for Nonlinear Optical Applications
Supervisor: Dr Stefano Palomba
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Fast transfer and processing of information are crucial to our modern society. They are
mostly carried out by a combination of electronics, for processing the information, and
photonics, for transmitting those light signals over long distances. However, these
traditional roles are not enough to fulfil the increasing demands for more and more
information. Light-based devices are taking over some of tasks traditionally carried out by
electronics such as the transfer of information between different circuit boards in large
computers (interconnects). Being able to take over some further tasks from electronics
requires light to interact with itself, which does not happen at low light intensities. If the
light intensity in an appropriate material becomes high enough, light interacts with itself,
generating, for instance, new colours (frequencies). These nonlinear phenomena are thus
light intensity dependent and are very weak. Two approaches have been explored to
exploit substantial nonlinear phenomena: (i) transparent materials like glasses or
semiconductors (photonics); (ii) opaque, absorbing materials like metals (plasmonics).
Both these schemes have advantages and drawbacks. An alternative approach combines
the best characteristics of metals and dielectrics into a hybrid structure, which exhibits
high light intensities, moderate losses and on-chip compatibility. The basic structure of
every on-chip photonic device is a waveguide. Therefore our basic hybrid structure is a
waveguide made of a nonlinear dielectric material (core), sandwiched between a metallic
layer (plasmonic structure) and another dielectric material. We call this a hybrid plasmonic
waveguide (HPWG).
Proposed work: This project involves the experimental test of various HPWGs we
fabricated based on our previous theoretical modelling and the first iteration of
experimental tests. You will be helped by our PhD student in charge of this project and
you will be trained to use our home built setup designed to perform these measurements.
This work will potentially lead to high quality publications.
Title of Project: Mastering vibrations in Graphene
Supervisor: Dr. Birgit Stiller, Dr. Amol Choudhary and Prof. Benjamin J. Eggleton
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
A single-atomic-layer graphene was extracted for the first time in 2004 for which the 2010
Nobel Prize in physics was awarded. Since then it has been branded as the ‘wonder
material’ and has attracted the interest of researchers worldwide due to its unique
properties in mechanics, optics, electronics and other domains. Various applications such
as super-strong materials, solar cells and new electronic devices prove the high relevance
of this material. In this project, you will investigate acoustic waves travelling through the
thin Graphene layers with help of stimulated Brillouin scattering (SBS), which is one of the
strongest non-linear interactions known to date. The latter is an acousto-optic interaction
that leads to forward and backward light scattering in optical waveguides. You will take
advantage of our expertise of integrated non-linear optics at CUDOS in order to test the
influence of Graphene on top of chalcogenide and silicon waveguides.
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Research Projects in Photonics and Optical Science
Title of Project: Sound waves in silk
Supervisor: Dr. Birgit Stiller and Prof. Benjamin J. Eggleton
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The ancient material silk is recently making a splash in the scientific community due to its
unprecedented properties for technological applications. Silk is fully bio-compatible, biodegradable and edible. With the ability to pattern silk - down to the nanoscale - and form
devices researchers were able to find new ways to e.g. deliver drugs into the human body
or sense diseases inside the body by harnessing the optical properties of silk. However,
the superior mechanical properties of silk just recently came to researchers’ attention,
reporting for the first time high frequency (several GHz) acoustic phonons in silk. The
group of Prof. Benjamin Eggleton is at the forefront of studying the interaction of acoustic
phonons and photons in waveguides. The techniques pioneered over the years here at
the school of physics can be used to investigate the mechanical properties of silk
waveguides and provide a deeper understanding of this truly beautiful material.
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Research Projects in Photonics and Optical Science
Research Projects in Physics Education
Title of Project: The measure of things
Supervisor: Tom Gordon
Co-supervisor: Manjula Sharma
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
In this project, you will compare different measurement devices against the
Measurement capabilities of a smart phone or tablet device. You will compare the
reliability, validity and accuracy of these devices against common measurement devices
used in the laboratory environment either at secondary or tertiary settings. This project is
suited to those interested in education and engagement in Physics. The project may also
include development and integration of measurement devices, applications and
techniques. This project is part of a government funded project on improving school
science. The findings from these projects are being used in workshops with school
teachers and students across the country, from Darwin to Armidale. They have the
potential to be published in journals.
Title of Project: Science inquiry: From demos, recipes to open investigations
Supervisor: Manjula Sharma
Co-supervisor: Tom Gordon
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Australian Government has funded a $2M national project to improve school science
education by researching ‘how to make better use of investigations’ to engage and excite
students as well as improve understanding. Your project will entail examining issues
ranging from:
 How often are investigations used?
 What is the nature of investigations carried out in school classrooms?
 Developing and evaluating experiments.
 Involvement in workshops across the country.
 Many other questions you can design
The findings from this project will being used in workshops with school teachers and
students across the country, from Darwin to Armidale. They have the potential to be
published in journals.
Title of Project: Topic of your choice
Supervisor: Manjula Sharma
Co-supervisor: Tom Gordon
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Sydney University Physics Education Research (SUPER) group can and does
undertake projects on topics ranging from misconceptions, multiple representations,
different ways of teaching to use of multimedia for teaching physics. Please contact us
and we will work with you in finding the right project for you. Check out our website for
possible topics to investigate.
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Research Projects in Quantum Physics and Quantum Information
Research Projects in Quantum Physics and Quantum Information
Title of Project: Numerical methods for simulating quantum spin lattices
Supervisor: Prof. Stephen Bartlett
Co-supervisor: A/Prof Andrew Doherty and/or Dr Steve Flammia
Email Contact: [email protected]
Brief Description of Project or Project Area :
Quantum spin lattice models (models of many quantum spins) are of immense interest in
the condensed matter and quantum physics communities. These models exhibit extremely
unusual (topological) collective quantum properties, making them promising candidates for
quantum computation. Analytical and experimental investigations of these models are the
subject of much research in the Quantum Science group.
Numerical simulations complement and expand our analytical understanding of these
models, as well as provide evidence of experimental signatures that are observable in the
lab.
These simulations are extremely challenging to design (such that they effectively capture
the quantum physics) and execute (such that they are feasible within current computing
capabilities). The numerical methods used are state-of-the-art algorithms and are
themselves under continual development, in order to better capture the quantum behaviour
of many-body spin systems.
This project would involve development of established numerical methods as well as
theoretical many-body physics research. This project would suit a student with a
programming/computer science background or inclination, as well as someone with an
interest in many-body quantum physics. The numerical investigation would make use of
MATLAB, C++ or python programming. The project may involve collaboration with or
supervision of other members of the Quantum Science group.
Title of Project: Theory of quantum computing using electron spins in
semiconductor nanostructures
Supervisor: Prof Stephen Bartlett
Co-supervisor: A/Prof Andrew Doherty
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The spin of a single electron can serve as a quantum bit or ’qubit’ – the basic element of a
quantum computer – provided we can trap it in place, manipulate it, and cause it to interact
with other spins in a relatively noiseless environment. Electrostatically-defined quantum
dots in a two-dimensional electron gas in a semiconductor provides a way to do this, and is
being pursued by the experimental group of Prof David Reilly as well as our collaborators
at Copenhagen, Harvard, Tokyo, and elsewhere.
We are offering a number of theory projects in this area including: (1) developing robust
and efficient methods to compute the wavefunction of the electron, and how well the
‘quantum logic gates’ can be performed, based on electronic measurements; (2)
understanding how the electron interacts with the nuclear spins in the semiconductor, with
a specific aim to ‘programming’ the nuclear environment to interact with the electron in a
specific way; (3) developing methods for quantum control of the electron; (4) designing
basic demonstrations for quantum algorithms to run on a simple quantum computer.
These projects can involve a mix of analytical mathematical methods as well as numerics
(Matlab).
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Research Projects in Quantum Physics and Quantum Information
Title of Project: Manipulating anyonic defects in two- and three-dimensional
topological models
Supervisor: Prof Stephen Bartlett
Co-supervisor: Dr Steve Flammia
Email Contact: [email protected]
Brief Description of Project or Project Area :
A topological model is a quantum many-body system with a ground state degeneracy that
depends on the topological properties of the lattice in which it is defined. Defects in these
models can behave as anyonic degrees of freedom – they don’t act as either bosons or
fermions, but acquire more general phases when braided around each other.
Such anyonic degrees of freedom as defects can encode quantum information, and we
can perform operations on this information by braiding the defects through a process called
code deformation. In addition, code deformation allows us to change the types of anyons
and even the dimensionality of the system (eg move from 2D to 3D in a local patch). We
will investigate how code deformation can perform interesting quantum operations in a
specific set of models known as colour codes.
Title of Project: Ion Trapping Hardware for Quantum Control
Supervisor: Associate Professor Michael J. Biercuk
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Quantum Control Laboratory is an experimental research group focused on the control
and manipulation of the internal states of trapped ions as model quantum systems. This
project will focus on the development of new ion trapping hardware specially suited to these
experiments, incorporating high optical access and access for microwave antennae used to
control the ion spin state.
The student will have the opportunity see the development of new experimental
infrastructure from the ground up, including the development of high-stability laser systems,
microwave and radiofrequency electronics, and ultra-high vacuum systems. This project will
be conducted within the new Sydney Nanoscience Hub.
Title of Project: Advanced Digital Hardware for Quantum Control
Supervisor: Associate Professor Michael J. Biercuk
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Quantum Control Laboratory is an experimental research group focused on the control
and manipulation of the internal states of trapped ions as model quantum systems.
Experimental systems are extremely complex and require the synchronization of many
disparate technical subsystems on nanosecond timescales. This project will focus on the
development of highly customized digital electronics for applications in experimental control,
laser stabilization, and the like. Efforts will be based on Field-Programmable Gate Arrays,
and will require strong programming capabilities.
This project will be conducted within the new Sydney Nanoscience Hub.
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Research Projects in Quantum Physics and Quantum Information
Title of Project: Quantum Control of Trapped Ytterbium Ions
Supervisor: Associate Professor Michael J. Biercuk
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Quantum Control Laboratory is an experimental research group focused on the control
and manipulation of the internal states of trapped ions as model quantum systems. In
particular, we are interested in studying new techniques to perform quantum logic
operations in a manner that is robust against errors. This can be accomplished through
the application of a special sequence of control operations designed to ``erase'' the buildup
of error due to uncontrolled environmental coupling. The project will focus on the
implementation of such control protocols using a special microwave system that permits
arbitrary manipulation of a Ytterbium atom's quantum state.
This project will be conducted within the new Sydney Nanoscience Hub. Experience
gained in this project will cover atomic physics, magnetic resonance, microwave systems,
and quantum control. Multiple projects are on offer within this heading.
Title of Project: Programmable Quantum Simulation in Ion Chains
Supervisor: Associate Professor Michael J. Biercuk
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Quantum Control Laboratory is an experimental research group focused on the control
and manipulation of the internal states of trapped ions as model quantum systems. We
have developed new experimental capabilities allowing the trapping and coherent
manipulation of chains of ions in a RF Paul trap. We are seeking to leverage new
theoretical concepts developed by our group in order to realize Programmable quantum
simulators capable of investigating the physics of quantum magnetism in a well controlled
experimental platform.
This project will be conducted within the new Sydney Nanoscience Hub. Experience
gained in this project will cover atomic physics, magnetic resonance, microwave systems,
and quantum control. Multiple projects are on offer within this heading.
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Research Projects in Quantum Physics and Quantum Information
Title of Project: Large-Scale Quantum Simulation in a Penning trap
Supervisor: Associate Professor Michael J. Biercuk
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Trapped atomic ions are a leading candidate system for experiments in quantum
simulation, through which we attempt to realize a controllable quantum system capable of
simulating more complex, uncontrolled quantum systems. This project will focus on the
development of quantum simulation experiments using large ion crystals in a Penning trap.
This effort will build on successful experimental demonstrations of quantum simulation
using 300 qubits, and will leverage new insights into the control of quantum systems.
This project will be conducted within the new Sydney Nanoscience Hub. This project will
incorporate experience in experimental atomic physics, charged-particle trapping, custom
experimental system design, and electromagnetic simulation. Multiple projects are on offer
within this heading.
Title of Project: Quantum Control Theory for Robust Quantum Computation
Supervisor: Associate Professor Michael J. Biercuk
Co-supervisor:
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The Quantum Control Laboratory is a research group focused on the control and
manipulation of the internal states of trapped ions as model quantum systems. Part of this
research activity requires the development of new quantum control techniques via
theoretical exploration. Our aim is to produce techniques which provide intrinsic
robustness against errors - a major problem in quantum computation and quantum
technologies broadly. This project will seek to develop and characterize the performance
of efficient control techniques that suppress the effects of environmental decoherence and
imprecise physical control systems.
This project will be conducted within the new Sydney Nanoscience Hub. Through the
project the student will learn quantum control, quantum information theory, and
fundamental experimental aspects of quantum physics. Multiple projects are on offer
within this heading.
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Research Projects in Quantum Physics and Quantum Information
Title of Project: Trilateration of quantum states
Supervisor: Dr Christopher Ferrie
Co-supervisor: Dr Steven Flammia
Email Contact: [email protected]
Brief Description of Project or Project Area :
In a grand irony, the exact same exponential scaling that gives a quantum information
processing device its power also limits our ability to characterize it. In short, an entirely
new paradigm of “quantum learning” is required. The proposed research is to generalize
and apply advanced methods from machine learning to develop efficient algorithms to
characterize new devices that operate in the quantum regime. The aim of this project is to
investigate some approaches to realize this new paradigm. We will generalize the idea of
trilateration (used for GPS navigation) to the problem of estimating quantum states. To
make this a scalable solution, we will require further to incorporate dimension reduction
ideas from many-body (tensor networks, for example). A primary goal of the project is the
implementation of the solution in the Python programming language.
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Research Projects in Theoretical Physics
Theoretical Physics Group
Title of Project: The rate of Kepler superflares
Supervisor: Mike Wheatland
Co-supervisor: Don Melrose
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Data from NASA's Kepler mission has been used to hunt exo-planets and for
asteroseismology, but it also allows identification of stellar flares, which cause transient
brightness increases in the light from individual stars (Maehara et al. 2012). These events
are the counterparts of solar flares - magnetic explosions in the Sun's atmosphere - but
they may be 105 times as energetic. Kepler has shown that stars of all spectral types
produce superflares (Balona 2015), and individual stars can be remarkably active,
producing dozens of events per day (Hawley et al. 2014). Superflares follow a similar
power-law size distribution to solar flares (Shibata et al. 2013), and they are also magnetic
in nature. This project will investigate the similarities and differences between the statistics
of stellar superflares and solar flares. It will examine the rate at which superflares occur for
individual stars, using the waiting-time distribution as a tool for understanding. The results
will be related back to the physical mechanisms believed to underlie stellar and solar
flares, and new ideas for the flare process being developed by the supervisors. The
project has scope for data analysis, theory and modeling.
Balona, L. 2015, Monthly Notices of the Royal Astronomical Society 447, 2714
Hawley S. et al. 2014, Astrophysical Journal 797, 121
Maehara H. et al. 2012, Nature 485, 478
Shibata K. et al. 2013, Publications of the Astronomical Society of Japan 65, 49
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Research Projects in Theoretical Physics
Title of Project: Electrical current systems and magnetic field topology in the solar
corona
Supervisor: Mike Wheatland
Co-supervisor: Don Melrose
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Large scale electrical current systems flowing in the ionised solar corona above sunspots
provide the energy for solar flares. Because of the high electrical conductivity of the
corona, the magnetic field is ``frozen in'' to the plasma and cannot change its connectivity,
except during the energy release process (magnetic reconnection) which causes flares. A
range of theory has been developed to describe coronal magnetic field connectivity, or
field topology. The connectivity of the field is defined by separatrix surfaces between sets
of field lines with different connectivity. These surfaces intersect in special lines
(separatrices) which begin and end on null points, where the field is zero. In the absence
of nulls it is possible to identify "quasi-separatrix layers" (QSLs), defined by large changes
in field line connectivity. "Bald patches" are regions where the field is tangent to the
photosphere (the solar surface) along a neutral line.
The theory describing magnetic topology has largely ignored the role of electric currents.
The coronal field is ``force-free'' due to the strong magnetic field and the low plasma
density, meaning that currents are everywhere parallel to field lines. However, the currents
may vary in magnitude and sign between different field lines. This project will investigate
the structure of electrical current systems and their relation to the field topology, using a
nonlinear force-free code applied to simple quadrupolar-field boundary conditions. The
project will involve a mix of theory, computation, as well as scientific visualisation of threedimensional vector fields. The numerical work will require use of an existing code, as well
as writing new codes to investigate field and current structures.
Title of Project: Circular polarization and Faraday rotation
Supervisor: Don Melrose
Co-supervisor: Mike Wheatland
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The radio emission from extragalactic radio sources is due to synchrotron emission which
is partially linearly polarized. As radio waves propagate through the interstellar medium
(ISM), the small difference in refractive index between left and right hand polarized waves
causes the plane of linear polarization to rotate. The sign of this Faraday rotation depends
on the sign of the projection, Bz, of the local magnetic field in the ISM on the ray path.
Extragalactic sources typically also have a small degree of circular polarization, whose
origin is uncertain. One model attributes the circular polarization to a propagation effect in
the ISM, arising from the regions where Bz reverses sign.
The project will involve integrating a matrix equation (for the Stokes parameters) along the
ray path through an idealized model for the region where Bz changes sign. The predictions
of the model will be compare with observational data.
Melrose, D. B. & McPhedran, R. C. Electromagnetic processes in dispersive media.
Cambridge University Press, 1991, p.189
Melrose, D.B. 2010, Faraday rotation: Effect of magnetic field reversals, Astrophys. J.,
725, 1600
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Research Projects in Theoretical Physics
Title of Project: Magnetar radiation belts
Supervisor: Don Melrose
Co-supervisor: Mike Wheatland
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
Magnetars are a class of pulsar-like neutron stars with exceptionally strong magnetic fields
and slow rotation rates. They are observed primarily from their high-energy emission, in
both Soft Gamma Repeaters (SGRs) and Anomalous X-ray Pulsars (AXPs). Outbursts on
SGRs are the most powerful known examples of magnetic explosions. A subset of
magnetars are also observed as radio pulsars. A favored model for the hard X-ray
emission from magnetars involves high-energy pairs trapped in closed magnetic field lines
(Beloborodov 2013). Such trapping is analogous to energetic particles trapped in the
Earth's radiation belts, also known as the Van Allen belts (Luo & Melrose 2008). There is
an extensive literature on how trapped particles are lost through precipitation into the
Earth's atmosphere.
This project will involve adapting models for the loss of trapped particles from the Earth's
radiation belts to trapped relativistic particles in a magnetar magnetosphere. A specific
question that will be addressed is: Do the trapped electrons and positrons precipitate, like
the terrestrial analog, or do they slow down and annihilate in the magnetosphere?
Observational implications of both possibilities will be explored.
Beloborodov, A.M., 2013, On the mechanism of hard X-ray emission from magnetars,
Astrophys. J., 762, 13
Luo, Q., Melrose, D.B., 2008, Pulsar transient radio emission, in Y.-F. Yuan, X.-D. Li, D.
Lai (eds) Astrophysics of Compact Objects, AIP Conference Proceedings 968, p.159
Title of Project: Current starvation in pulsar magnetospheres
Supervisor: Don Melrose
Co-supervisor: Mike Wheatland
Email Contact: [email protected]
Brief Description of Project or Project Area (5 – 10 lines long):
The electrodynamics of pulsars remains inadequately understood (Melrose & Yuen 2016).
In a corotation model, the plasma around the neutron star is assumed to be rotating at the
same angular velocity as the star. Corotating plasma implies a corotation electric field
whose divergence implies a corotation charge density. “Charge starvation” refers to
conditions under which the plasma cannot supply the required charge density, implying
that the plasma cannot be corotating. In an oblique rotator, corotation also implies a
corotation current density, and “current starvation” refers to conditions under which the
plasma cannot supply the required current density (Melrose & Yuen 2016). Unlike charge
starvation, the implications of current starvation for pulsar physics are yet to be explored.
This project will involve reviewing pulsar electrodynamics, modelling the conditions under
which current starvation is likely to be significant, and discussing possible observational
consequences.
Melrose, D.B., Yuen, R. 2016, Pulsar electrodynamics: an unsolved problem, J. Plasma
Phys., 82, 635820202
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