Applications are invited for a postgraduate research position leading to a PhD degree in Electrical Engineering in the Institute for Digital Communications within the School of Engineering at the University of Edinburgh.
This project focuses on modelling the phenomena occurring when polychromatic (poly-energetic) energy is driven into various media, with the intent to utilise measurements of this energy for spectral image reconstruction. In the GHz-THz frequency band these photon-matter interaction phenomena include predominantly attenuation due to the photoelectric effect and small angle scattering due to Thomson and Compton scattering. The physical laws underpinning these scale-dependent phenomena are geometric optics under the complex refractive index formalism. Advances in instrumentation technology now allow one to measure this radiation (say in the form of X-rays or lasers) as it exits the media of interest on hyperspectral detectors with spatial and spectral resolution. In contrast with conventional monochromatic, linear attenuation tomography, these information rich data are used to reconstruct the spectrum of the image at specific energy bands to reveal the composition of the target in various chemicals. Such information can then be linked to the presence of defects into materials, concealed explosives or classify human tissue pathology such as calcification and tumours. The image reconstruction will follow in the direction of Radon transform inversion but with an emphasis on exploring techniques for limited angle data. In contrast to the conventional attenuation models, photon-matter interactions from polychromatic sources have recently been shown to comply with nonlinear attenuation models and thus adaptations to Fourier-based image reconstruction algorithms will be sought, preferably in the form of efficient algebraic reconstruction algorithms that involve regularisation.
This exciting, interdisciplinary research is at the intersection of physics, scientific computing and imaging science, with many potential applications in medical and materials imaging, as well as security applications. The project will benefit from collaboration with industrial partners and academic collaborators with expertise in instrumentation and data acquisition experiments.
- John Weiner, P.-T. Ho, Light-Matter Interaction, Volume 1, Fundamentals and Applications, Wiley, 2008.
A first class Honours degree (or International equivalent) in engineering, physics, informatics or applied mathematics, ideally supplemented by an MSc Degree.
Further information on English language requirements for EU/Overseas applicants.
Competitive funding subject to availability.
Nick Polydorides, Agile Tomography Group Leader, firstname.lastname@example.org