Current Student Research
Christopher Bostock – 1st year PhD student and GTA
Project: Spontaneous spatial fractal pattern formation in simple optical cavity systems
I read Physics for both my BSc and MPhil degrees at Salford, and finally decided to stay on to undertake a PhD. I'm currently researching complexity theory, studing spontaneous spatial fractal formation in non-linear optical systems. Fractals are patterns with comparable levels of detail that persist across many decades of scale (so that as you look closer and closer at any part of the pattern, more and more detail becomes visible). Research at Salford (in 2005) proposed a universal signature for predicting the spontaneous emergence of fractal patterns in wave-based non-linear systems. This mechanism has its origins in the seminal work of Alan Turing in 1952.
As I'm on the GTA programme, part of my working week is devoted to teaching duties. I'm a postgraduate demonstrator in the computing laboratories, typically helping students to understand non-linear dynamical systems using MATLAB programming. Demonstrating can be quite a challenging role - explaining new (and often quite subtle) concepts that are so unfamiliar to undergraduate audiences, but which I encounter every day! In this sense, the GTA scheme has provided a good way of improving my communication skills. I then get to test out these new skills when presenting my work at conferences.
Helen Christie – 1st year PhD student
Project: Molecular dynamics simulations of radiation-induced damage defects in graphite
Molecular dynamics simulations are used to study damage defects in graphite after it has been irradiated. These studies reveal vacancies and interstitials present in the irradiated graphite, showing the effect they have on the overall structure.
There are three areas of interest in the graphite simulations. The first occurs in the swift heavy ions. A primary knock-on atom (PKA) passes through a region without colliding with any atoms. It transfers electron energy to the surrounding atoms, causing them to vibrate and resulting in the formation of interstitials and vacancies. The second area of interest is the cascade region. The PKA hits one or more atoms, resulting in the displacement and collision of other atoms within the cell. The final area looks at the vacancies and interstitials created by the cascade. The irradiated graphite simulations must be tested in a variety of environments.
Graphite behaves very differently from other carbon materials. In order to understand the unique nature of graphite, I'm simulating an assortment of carbon materials (such as diamond and glassy / amorphous carbon). I've recently come back to Salford after a three-month sabatical, learning new computational techniques with our collaborators at the Curtin University of Technology in Perth, Australia.
Abi Heyes – 2nd year PhD student
Project: Magnetic effects and chiral patterns in photonic structures
It has been demonstrated that light diffracted from a dielectric planar chiral surface undergoes rotation of the polarisation azimuth in the first order beam. The effect is dependent on the sense of chirality of the surface. This work has been extended to show changes in the polarisation state when light is transmitted through a planar chiral structure.
My PhD aims to extend this effect further by performing experimental investigations to identify parameters that can be adjusted to optimise polarisation rotation, such as the type of chiral pattern or the spacing between patterns in the array. Our group is also attempting to observe the effect in a magnetised chiral structure, and to characterise the role magnetisation has on the degree of rotation. The surfaces are patterned using a focused ion beam, and we use Stokes polarimetery to analyse the effect on the incident light.
Emily McCoy – 2nd year PhD student
Project: Propagation of Helmholtz spatial solitons in patterned non-linear optical structures
I am currently researching the properties of spatial solitons (self-trapped beams of light) when they interact obliquely with the interface between dissimilar non-linear dielectric materials. This class of problem is crucial in the design of essentially any future integrated-optic device architecture.
My research is a blend of mathematical analysis and computer simulations. In my first year of PhD study, I started out by looking at soliton scattering at a single interface. I'm now in my second year, and have recently been developing new beam propagation models to predict how spatial solitons can be coupled into more exotic optical structures such as waveguide arrays and photonic crystals. Studies of these geometries have, historically, been hampered by the "paraxial approximation". Our research allows this approximation to be entirely lifted, and we have made a raft of new physical predictions about phenomena that are directly observable in the laboratory.
One aspect of the PhD that I've particularly enjoyed is attending conferences. Having the opportunity to present my work, and to see what other research is going on in the photonics community, has been an exciting experience. It also helps in gaining confidence with public speaking (an important part of many jobs today).
Alice Bailey – 3rd year PhD student
Project: The study of graphitic materials using poly-CINS analysis
Graphitic materials are of interest in several areas of physics, such as a moderator in some nuclear reactors. Hence, studying natural graphite can give us valuable information about the potential lifespan of reactor graphite. Graphite-based materials are also under active investigation as a host material for hydrogen storage applications. C60 intercalated graphite has been proposed as a potential candidate, due to the increased pore size created by the C60.
The properties of graphite-based materials can be probed experimentally using the polycrystalline Coherent Inelastic Neutron Scattering (poly-CINS) technique. This particular method tends to yield information about the phonon modes of a material, and it also allows one to infer structural characteristics.
The poly-CINS technique is relatively novel and requires analysis of large complex data sets. My PhD has been focused primarily on developing a software suite ("Neutronplot") to aid with the visualisation and interpretation of these data sets. To this end, I have been able to attend several relevant training courses at the Universities of Oxford and Warwick. What makes our approach different from other software packages is that we can now provide a full comparison between the predictions of various theoretical models and the poly-CINS data obtained from neutron-scattering experiments.
Christopher Pawley – 3rd year PhD student
Project: The use of in-situ ion-irradiation / TEM techniques to simulate neutron induced radiation damage in SiC
A collaboration between the MIAMI facility (University of Huddersfield), Institut Pprime (University of Poitiers, France) and the JANNuS facility (CSNSM Orsay, Paris) has allowed us to utilise the only two in-situ ion beam microscopy facilities in Europe. The purpose of this collaboration is to exploit the capabilities of the two facilities to collect a unique set of data, simultaneously combining expertise in ion irradiation with knowledge in microscopy of silicon carbide (SiC) and its behaviour under irradiation. MIAMI can irradiate with high fluxes of light elements (e.g., helium), which allows us to observe the nucleation and growth of helium bubbles while maintaining the same irradiation and microscopy conditions throughout. JANNuS irradiates with high-energy heavy elements (which has the effect of imparting damage into the crystal structure), providing insight into the behaviour of SiC (and the helium bubbles within) under simulated irradiation from neutrons.
My research aims to provide information about the nucleation and growth of helium bubbles in SiC, and about the behaviour of both SiC and helium bubbles under high-energy displacing irradiation. The motivation behind this research is to assist the nuclear community in making decisions about nuclear design in the coming years.
Christopher Quinn – 3rd year PhD student
Project: Experimental study of the thermal effects in thin-film ferromagnetic binary alloys
My research areas cover magnetic properties and crystallographic structures of thin films and ribbons, and how thermal influences upon them manifest themselves as either magnetic changes, structural differences, or a combination of the two.
The work I undertake involves a variety of ferromagnetic alloys, particularly iron-based binary alloys. I am currently researching Galfenol (a magnetostrictive alloy consisting of iron and gallium). We have to fabricate several compositions of material, either by physical vapour deposition or melt-spinning, and then use a range of techniques to characterise them. The majority of experiments we undertake are performed using in-house facilities at the University.
The methods I use incude transmission electron microscopy (to examine internal structure), scanning electron microscopy (to observe surface effects), x-ray diffraction (to identify lattice parameters and phase differences) and vibrating scanning magnetometry (to measure magnetisation). We also perform diffraction experiments at neutron facilities such as ISIS, Oxfordshire, and Institute Laue-Langevin, Grenoble.
All our experiments can be coupled with thermal treatments in-situ. It is therefore possible to monitor any changes in real time, and to record accurate data sets that may subsequently be used in the analysis of our samples.
GTA Student Profiles
Gael Baldissin – 3rd year PhD student and GTA
Project: Ordering/disordering phenomena in materials
My interest has been focused on studying ordering/disordering phenomena in a wide range of materials: palladium hydride, Ti-Mn based Laves phases, carbon based materials with heteroatom substitutions, and the Li-N-H system for energy storage. Understanding the configurational properties and phenomena related to order/disorder transitions are of fundamental interest for novel applications. The approach has been mainly computational, using density functional theory calculations coupled with the cluster expansion method to map interactions onto a computationally tractable scale. For the Li-N-H system, a series of experiments have been performed involving neutron powder diffraction at ISIS (Didcot, UK), x-ray powder diffraction at ESRF (Grenoble, France) and at Diamond (Didcot, UK).
I have been in charge of a research computational cluster as the Linux System Administrator, providing me with the opportunity to improve my skills in high-performance computing, a field that is gaining increasing importance in industrial and research facilities.
As a Graduate Teaching Assistant (GTA), I devote part of my work to support teaching for undergraduate students, both in practical laboratory sessions and in computer programming. This has been an invaluable experience that has helped me to improve my communication skills in a foreign language (English) and to revise concepts of basic physics.
Training and Skills
The University offers all postgraduate research students an extensive range of free training activities to help you develop your research and transferable skills. Research seminars and participation in conferences will also be offered to you.
All postgraduate research students are expected to attend the College’s research methods seminars during your first year of study, covering subjects such as conducting a literature review, methods of data collection, research governance and ethics, along with analysis, presentation, interpretation and rigour in qualitative research.
The Salford Postgraduate Research Training (SPoRT) programme has been designed to equip researchers both for your university studies, and for your future careers whether in academia, elsewhere in the public sector, or in industry and the private sector.
The University further runs two separate annual conferences – SPARC (Salford Postgraduate Annual Research Conference) and the Doctoral Training School Conference – to provide its postgraduate researchers with the opportunity to hone your research presentation skills within a friendly, informal environment.
As a postgraduate research student at the University of Salford, you are required to meet a number of milestones in order to re-register for each year of study. These ‘progression points’ are an important aid for both you and your supervisory team and it is essential that you complete them on time.
Learning Agreement: this is completed by you and your supervisor collaboratively in the first 3 months of your research programme. It encourages both of you to develop a thorough and consistent understanding of your individual and shared roles and responsibilities in your research partnership.
Annual Progress Report: this report is completed by your supervisor at the end of each year of study, and reports on your achievements in the past year, the likelihood that you will submit on time, confirmation of the Learning Agreement and relevant training undertaken.
Self Evaluation Report: this is completed by you at the end of each year of study. It asks you to comment on your academic progress, supervisory arrangements, research environment, research training, and relevant training undertaken.
Interim Assessment: this is an assessment of your progress by a panel. It takes place towards the end of your first year, and is designed to ensure you have reached a threshold of academic performance, by assessing your general progress. The assessment comprises a written report, presentation and oral examination by a panel. You must successfully complete it in order to register for your second year.
Internal Evaluation: this will take place towards the end of the second year and successful completion is required in order to continue onto your third year of study. You will be expected to show strong progress in your PhD study - reflected in the submission of a substantial piece of work, generally at least 4 chapters of your thesis.