Physics and Optoelectronics Honours Degree Projects
Below is a list of possible Honours projects currently available. The title and brief description are listed as well as the project supervisor(s) who should be contacted for further details. In addition to the projects listed below, further projects are possible, and you should feel free to talk directly to staff members about your interests and potential research topics.
The closing date for Honours applications is 31 October 2007, and the application form is available at the Student Centre. Full-time students enrol in the units named OPTO400 (D3) or PHYS495 (D3). Please contact the Honours Convener prior to this date if you are interested in pursuing the Honours degree or if you have any queries.
Click on Physics staff member's name to go directly to project details:
| Staff Members (Click to see suggested projects) | Project Areas |
| Associate Professor Gavin Brennen | Quantum computation |
| Dr Peter Browne | Laser physics, nonlinear optics, Sol-gel coatings, Optical properties of materials |
| Associate Professor David Coutts | Micromachining, polymer dye lasers, high speed imaging |
| Dr Jim Cresser | Quantum Optics |
| Associate Professor Judith Dawes | Laser physics, medical physics |
| Dr James Downes | Novel semiconductor physics |
| Dr Alex Fuerbach | Laser physics, non-linear optics |
| Professor Deb Kane | Laser physics, optical physics, materials processing |
| Professor Brian Orr | Spectroscopic sensing, using tunable lasers and nonlinear optics |
| Dr Quentin Parker | Astronomy |
| Dr Helen Pask, Dr Richard Mildren & Professor Jim Piper | Laser physics, optical physics |
| Professor Jim Piper | Laser physics |
| Dr Jim Rebeau | Quantum Materials and Applications |
| Dr Daniel Terno | Quantum Information Theory |
| Professor Jason Twamley | Quantum Science, Mesoscopic Physics/Technology, Laser Physics |
| Associate Professor Mark Wardle | Astrophysics |
| Dr Mick Withford | Laser based fabrication of microstructures |
| Associate Professor Andrei Zvyagin | Laser based spectroscopy |
Supervisor: Associate Professor Gavin Brennen
Protected quantum memories and ground state computation
A continuing challenge for implementing quantum computation is to reduce the effect of noise during gate operations and due to environmental interactions. One appealing solution is to store quantum information in the degenerate ground subspace of a many body Hamiltonian. The preparation will be robust if the logical states are stable under environmental noise which can be established if there is an energy gap between the code space and excited states and if the logical operations themselves are non local in nature. In this project we will investigate issues with engineering many body Hamiltonians for subsystem codes or surface codes, preparing ground states either adiabatically or by reservoir engineering, and processing the information e.g. via the one-way model. Emphasis will be made on realizations with atoms or dipolar molecules trapped in optical lattices.
Supervisor: Associate Professor Judith Dawes
Femtosecond laser dentistry
Building on our previous work on femtosecond laser dentistry for ablation of decay in teeth, we will study the effect of laser irradiation on the acid resistance of healthy dental enamel and dentine. This has potential for improving the resistance of teeth to decay. We collaborate with a dentist in private practice, to ensure that our results have clinical relevance.
Surface plasmon circuits
Surface plasmons are optical-electronic excitations that propagate along metal-dielectric interfaces. We aim to develop simple circuits that can transfer signals based on amplifying media. We will design and fabricate a device and characterise its performance using a near field optical microscope.
Supervisor: Dr James Downes
Growth and characterisation of rare-earth nitride magnetic semiconductor thin films
Recent theoretical work has shown that rare-earth metal nitride compounds are expected to be metals, half metals, half semiconductors, or insulators depending on the choice of metal. Half semiconductor materials are potentially useful in the construction of 'spintronic' devices - electronic devices that utilise the spin of an electron to carry information. Using local metal organic chemical vapour deposition (MOCVD) equipment we will deposit thin-films of several rare-earth nitride semiconductors. We will then characterise the electronic/optical and mechanical properties of these films.
Photo-bleaching of organic semiconductor thin films used in OLED devices
A new generation of semiconductors based on organic molecular solids is currently being developed for use in light emitting diode (OLED) displays. A current problem limiting the practical use of these materials is how to lithographically pattern them (in a similar way Si is patterned to create integrated circuits). Selective photo-bleaching of thin-film material may provide a means to perform this patterning. We will study experimentally the effect that high-intensity ultraviolet light exposure has on the electronic/optical properties of several materials used in the construction of OLED devices.
Supervisor: Dr Alex Fuerbach
Chirped-pulse supercontinuum generation.
Supercontinuum generation is a process where laser light is converted to light with very broad spectral bandwidth (white light), while the spatial coherence usually remains high.
Applications of supercontinua include frequency metrology, optical coherence tomography and fluorescence microscopy.
Chirped-pulse oscillators are a novel type of lasers generating strongly chirped high energy laser pulses, which can be compressed down to only a few femtoseconds (1 fs = 10^-15 s) in duration.
The aim of this project is to use a special type of optical fibre (Photonic crystal fibre, PCF) to temporally compress the output pulses of a chirped pulse oscillator, thereby generating high power supercontinuum radiation. Numerical simulations should top the work off which is very likely to result in a peer-reviewed journal paper.
Supervisor: Professor Deb Kane
Physical Optics and related studies of Australian Spider Web Silk
There has been considerable interest in the mechanical properties of spider silk – with the draglines of orb-web spiders being considered the toughest natural fibre. Little has been done in researching the refractive and diffractive optics of web fibres, and how this relates to the micro and nano-structure of the fibres themselves. “Dew” bows have been documented but these do not explain many of the optical effects readily observable in a spider web in sunlight from various angles of illumination. This project will study the optics and structure of spider web fibre using geometrical and physical optics approaches, and a range of optical microscopies and electron microscopy in structural analysis. Dr Marie Herberstein of the Dept of Biological Sciences will advise on spider species, web harvesting, and modification of spider silk by controlled diet.
Chaotic Semiconductor Lasers for Secure Communications
The development of semiconductor lasers with optical and optoelectronic feedback as sources of high dimensional chaotic output is currently a very active area of research by virtue of potential application in secure communications systems. In this project novel, two-section, quantum-dot, semiconductor lasers, fabricated by collaborators at ANU and in the States, will be studied as chaotic semiconductor laser sources. The project will involve laser physics, optics, and nonlinear dynamics.
Optical Near Field Techniques for Measuring Ultrafast Dynamics of Surfaces
In laser materials interactions such as, for example, using short pulsed lasers to remove sub-micron contaminant particles, the surface is predicted theoretically to oscillate at frequencies of the order of 50-100 MHz. These oscillations are of a very small size (few angstroms to a few nanometres) and no technique has so far been developed to allow them to be directly observed. As a step towards developing such a technique this project will use near field probe techniques to measure electrically excited motion of piezoelectric materials. Once developed the technique will be generally applicable to a raft of nanoscience and nanotechnology applications.
Laser Cleaning for Indigenous Australasian and Pacific Island Cultural Heritage Conservation
Laser cleaning has long been used in art and cultural heritage conservation internationally with recent high profile conservation projects including the laser cleaning of the statue of David in Florence. The techniques is just beginning to be applied to items of cultural heritage significance in the Australasian and Oceania context. An initial project on laser cleaning of Aboriginal bark paintings and related conservation issues, in cooperation with the NSW Art Gallery and the Australian Museum has just commenced. The physics of the materials/laser interactions, relevant to cultural heritage applications, parallels that which arises in “more scientific” contexts.
Supervisor: Dr Jim Rebeau
Measuring single colour centres in diamond
Diamond, which is cubic crystalline carbon, also consists of many other atomic inclusions including Nitrogen, Nickel, Silicon and Boron to name a few. Some of these “defects” are very useful for studying quantum effects in matter. In particular, single colour centres are able to emit single photons when excited with a laser pulse. Single photons are true single quantum states and lead into exciting areas such as Quantum Cryptography and Quantum Computing. The Quantum Materials and Applications lab is trying to understand how to fabricate and control such colour centres by growing and measuring fluorescence in diamond.
Supervisor: Dr Daniel Terno
Problems in relativistic quantum information - quantum communication and entanglement between accelerated reference frames.
The relationship between information and physics has been an intriguing problem for many years. It took a new twist with the emergence of quantum information theory whose paradigm “information is physical” added a new point of view to old questions. Quan-tum information theory usually involves only a nonrelativistic quantum mechanics. However, both for the sake of logical completeness and in order to derive physical bounds on information transfer, its processing, and the errors involved, a full relativistic treatment is required. Additional motivation to relativistic extensions of quantum information theory comes from quantum cosmology.
Quantum field theory in curved spacetime, and black hole physics in particular, present challenges that everybody who upholds the principle that “information is physical” should respond to.
Supervisor: Professor Jason Twamley
Slow light
Slow light is an intriguing new phenomena where researchers can alter the physical properties of a medium so that a pulse of light, normally traveling at 30,000,000m/sec, in vacuum, is slowed down within this medium to only meters per second or indeed stopped completely. This effect has been demonstrated in atomic gasses and in solid state. This phenomena might allow one to manipulate light pulses to achieve all-optical switches and ultra-sensitive measurements via these slow-light pulses. In this project we will examine the emission of light from within such a medium by an emitter which is moving faster than the slowed down speed of light in this media. This might lead to highly non-trivial effects where the emitter could get "in front" of the photons it previously emitted, and to possibly interact with them again at a later time. Such a study may reveal new insights and uses for novel relativistic effects in quantum information science.
Joint supervisors: Professor Igor Sharlinski (Computing), Professor Jason Twamley
Shor's Factoring Algorithm
It is now a common knowledge that Shor's algorithm can factor
integers in polynomial time. However, in order to be practical
(even assuming that quantum computers are readily available)
this polynomial dependence should be of low degree. The project
will concentrate on evaluating several recent attempts (successful
and unsuccessful) to give a precise analysis of Shor's
algorithm and maybe introduce some improvements.
Joint supervisors: Dr Dominic Berry, Professor Jason Twamley
Phase estimates based on multiple measurements
Independent measurements of phase using a single photon in an interferometer can be combined to give an overall phase estimate. If this is done by an average, the resulting variance is twice as high as that obtained from using optimal phase estimates derived from Bayesian analysis. This extraordinary result means that taking the average is not the best way to combine measurement results. The goal of this project is to determine the cause of the increase in the phase variance, and if possible to find methods for more efficiently combining the results of independent phase measurements.
Multiple pass phase measurements for time standards
Recent experiments demonstrate that interferometry involving a variable number of passes through a phase shift allow the phase to be measured with accuracy at the Heisenberg limit. The total phase shift with multiple passes is taken to be p*phi, where p is the number of passes (an integer) and phi is the magnitude of the individual phase shifts.
The goal of this project is to generalise this technique to the case where the total phase shift is t*phi, where t may be a noninteger real number, and determine if the technique may be applied to time standards.
Bidirectional communication
It has been shown that there exist unitary operations which may be used effectively to create entanglement, but only allow a small amount of communication in one direction. The known example does allow significant communication in the other direction, however. The goal of this project is to determine an example allowing significant entanglement creation, but limited classical communication in either direction.
Joint supervisors: Dr Alberto Carlini, Professor Jason Twamley
Time optimal quantum computation and geometry
The time optimal approach to quantum computing may be of paramount relevance for the practical design of fast elementary gates and for the actual realization of subroutines and full quantum algorithms.
Determining the optimal time dependence of the physical coupling parameters (e.g., the strength of a magnetic field, the duration of a laser pulse) in the Hamiltonian which steers the physical system and expressing the cost of the experiment in terms of physical resources (e.g., the time required for the steering, the energy available in the experiment, the fidelity with which the target is reached) provides a more practical description of quantum algorithms than using gate complexity (the number of elementary gates necessary to build the quantum algorithm), which is a more abstract concept where physics is still implicit.
Furthermore, a geometric approach, by exploiting the continuous and local properties of curved manifolds (where quantum states and operators live and evolve), may pave the way towards a more systematic approach to novel quantum algorithms and thus uncover the true power of quantum computing.
Supervisor: Dr Mick Withford
Honours Projects with ARC Centre of Excellence: CUDOS
Design, fabrication and characterisation of waveguide mode converters
Supervisors Drs Michael Withford and Graham Marshall
The student will design and model waveguide mode converters whereby the
refractive index of the core or cladding is artificially varied. Direct
write -femtosecond laser techniques will be used to fabricate these inside
bulk glass and the devices characterised and compared with theory.
Investigation of femtosecond laser written polarisation maintaining
waveguides
Supervisors Drs Michael Withford and Graham Marshall
The student will create polarisation maintaining waveguides in bulk glass
using direct write-femtosecond laser fabrication techniques. The project
includes advanced characterisation, optimisations and theoretical
analysis.
Supervisor: Associate Professor Andrei Zvyagin
Background-free optical imaging of biological macromolecules and nanoparticles
In most cases in optics, imaging resolution is limited to roughly the wavelength of light. At the same time, the optical detection sensitivity of individual particles is unlimited theoretically. It is limited practically by the ratio of wanted versus unwanted photons, called background. The better this ratio, the better the background is suppressed, the smaller particles are detectable, be so nanoparticles or large biological molecules, e.g. proteins. An honours project will contribute to realisation of this detection principle, where a student will acquire experience in optics, electronics, and signal/image processing will be gained. Click here for more details.
Application of multiphoton microscopy to study of collagen regeneration
Multiphoton microscopy (MPM) is a new imaging method, which enables exquisite imaging of live cells and biological tissue. The key subsystem is a (very short pulsewidth) femto-second laser whose radiation is tightly focussed in a biological specimen, so that optical intensity becomes enormous for a short time of the pulse duration. This elicits non-linear optical response from the biological matter, which entails the most valuable property of this new microscopy, "optical sectioning", i.e. clearing a micron-thin image slice from the turbidity of the rest of the specimen.
In this project, we intend to apply MPM to image collagen-abundant tissue, such as cartilage and/or connective tissue, relying on a strong second-harmonic signal from collagen. In collaboration with the medical and laser physics researchers, we will investigate, yet mysterious, mechanisms of collagen regeneration under the exposure to the laser light. Understanding these mechanisms will have tremendous impact on the current practice of treatment of osteoarthritis and the related disease. Click here for more details.
Application of luminescent nanodiamonds to intracellular imaging
Imaging at the molecular level has recently become a reality, if specific molecular sites are tagged with "optical labels", so that even an individual molecule becomes visible in the cell. These optical labels can be engineered as organic dyes, quantum dots, or luminescent nanocrystals. Our research is focussed on the latter, i.e. luminescent nanodiamond (LND). LND is a diamond nanocrystal with a colour centre, which renders nanocrystal highly visible in the cell, even on the background of the cell's own fluorescence, called autofluorescence.
We have carried out collaborative research into production, characterisation of luminescent nanodiamonds, and LND-assisted intracellular imaging.
An honours student will carry our research into characterisation, e.g. sizing, and imaging of LNDs.
Please speak to the Honours Convener or any of the physics staff members listed above if you are interested in pursuing an honours degree.