This thesis is comprised of X-ray and optical studies of 27 X-ray selected galaxy clusters from the XMM-LSS survey. These systems are mostly groups and poor clusters, with temperatures 0.6-4.8 keV, spanning the redshift range 0.05 to 1.05, hence these are some of the highest red…
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In this work we present spectroscopic studies of the exciton dynamics in colloidal spherical cadmium sulfide CdS nanocrystals (NC) in the vicinity of a single indium gallium nitride InGaN quantum well (QW) in dependence of temperature. QWs of the alloy material InGaN exhibit a d…
A multiwavelength analysis of M31’s globular clusters and their low mass X-ray binaries by Mark B. Peacock Globular clusters (GCs) are dense groups of thousands to millions of stars. They are often very old systems with ages similar to those of their host galaxies and the early …
The thesis is focussing on the interaction of lithium niobate with UV and ultrafast laser radiation to achieve 1) ferroelectric domain inversion, 2) waveguide fabrication, and 3) surface microstructuring. Preferential ferroelectric domain inversion has been demonstrated by 'late…
In this thesis, polariton dynamics in GaAs semiconductor microcavities are investigated. Insertion of layers of active material within a Fabry-Perot resonator leads to strong coupling between excitons and photons, giving rise to new eigenmodes called excitonpolaritons. Bose-Eins…
This thesis is concerned with the deposition, and characterisation, of semiconductor thin films and microstructures deposited from a supercritical uid. Thin films of CdS, GaP, InP, InAs, and Ge were deposited using supercritical CO2 and CO2-solvent mixtures. Ge was deposited int…
This work presents a large scale multifractal analysis of the electronic state in the vicinity of the localisation-delocalisation transition in the three-dimensional Anderson model of localisation using high-precision data and very large system sizes of up to L3 = 2403. The mult…
The focus of this work is to investigate the effects of applying an external magnetic field to a solidifying liquid metal melt. The principle is that thermoelectric currents that are naturally inherent to solidification processes will interact with this magnetic field, resulting…
We present a study of the theory and simulation of Liquid Crystals. A general introduction to the field is given, then the essential features of the Monte Carlo (MC) sampling algorithm are described and explained, along with some of the practical considerations in the implementa…
This thesis discusses a comprehensive study of the structure and properties of selected stacked perovskites using non-ambient powder and single-crystal x-ray diffraction, powder neutron diffraction, birefringence microscopy and dielectric spectroscopy. The major portion of this …
T2K is an off axis neutrino beam experiment with a baseline of 295 km to the far detector, Super-Kamiokande. The near detector, ND280, measures the flux and energy spectra of electron and muon neutrinos in the direction of Super-Kamiokande. An electromagnetic calorimeter constru…
The purpose of work was to obtain gold and possible other negative ion cluster beams where each constituent atom in the cluster carried an energy ≤ 1 keV, using the floating low energy ion gun (FLIGTM), and to test these in secondary ion mass spectrometry. The heavy negative met…
An investigation was made into techniques that could be employed to produce sub-100nm wide superconducting nanowires. Nanowires of niobium and Y Ba\(_2\)Cu\(_3\)O\(_{7-δ}\) (YBCO) were fabricated in thin films using focused gallium ion beam milling (FIB) to a range of widths (10…
The objectives of this research were to investigate the possibility of controlling the '/' phase ratio and morphology in Sialon ceramics. These objectives have been sought by the control of the starting composition, and by post sintering heat treatment. The main emphasis has bee…
The "classical" laser-flash method is today the most used technique to measure the thermal diffusivity of a wide range of materials. This work describes the development of a new technique, based on the laser-flash method, which measures simultaneously on the same sample with an …
This work describes the preparation and the determination of some properties of two magnesium SiAlON ceramics, one with a low substitution level and one with a high substitution level ' phase. Each had a specific amount of spinel as second phase which would form on sintering or …
Silicon germanium alloy layers can be grown epitaxially on a silicon substrate to provide a means of adjusting the lattice parameter of the crystal. Such a platform, known as a virtual substrate, has a number of potential applications. For instance, it allows for subsequent over…
The relaxation of variable thickness strained silicon layers on 20% and 50% germanium composition virtual substrates have been quantified using two independent methods. High resolution X-ray diffraction offers a means to measure relaxation directly, and a defect etching techniqu…
It is now apparent that the continued performance enhancements of silicon metal-oxide-semiconductor field effect transistors (MOSFETs) can no longer be met by scaling alone. High-mobility channel materials such as strained Si1-xGex and Ge are now being seriously considered to ma…