Photovoltaic solar cells (PVs) are now recognised as the world’s fastest growing energy technology, yet, they only account for a mere fraction of current global renewable power capacity. It is acknowledged that this inadequate market penetration has been largely a result of the …
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A new class of metamaterials exhibiting coherent, collective response has been introduced. It is shown that the sharp resonant behaviour of coherent metamaterials can only be observed in arrays of metamaterial elements and is absent from the response of a single isolated unit ce…
Sol-gel derived bioactive glasses are promising candidates for bone regeneration, where bone is a natural nanocomposite of collagen (organic polymer) and hydroxyapatite (inorganic mineral) with a complex hierarchical structure and excellent mechanical properties. Solid-state NMR…
Quantum interference in atomic media has elicited interest for a very wide range of investigations and applications. As well as being a fascinating effect in itself, it also found applications in spectroscopy, nonlinear optics and has recently been drawing attention in the field…
This thesis presents an investigation into the morphology of palladium (Pd) size selected clusters and industrial Pd catalysts using high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) technique. The driving force of this work is to establish rel…
This thesis describes how for the first time, unidirectional operation and coupled ring tuning were realised on a quantum cascade laser material; specifically on a new strain compensated In0.7Ga0.3As/AlAs0.6Sb0.4 grown on InP substrate and operates in pulsed mode in the 3-4 micr…
The technique of medium energy ion scattering (MEIS) can be used to elucidate the structural details of surfaces, both in general terms and in a more qualitative manner, in order to help solve a number of outstanding uncertainties relating to the structures of a number of surfac…
Well known multiferroic compounds TbMnO3 and DyMnO3 show a strong coupling between antiferromagnetism and ferroelectricity. Magnetic susceptibility data for both compounds have been taken, showing large magnetic anisotropy, and providing strong evidence for the existence of crys…
In this thesis, we consider the noise properties of a Coulomb blockaded quantum dot weakly coupled to two non interacting leads. We consider two approaches to calculating the density of states of the quantum dot, the first of which uses a functional integral approach which is di…
The International Linear Collider (ILC) is intended to be a new high precision electron-positron collider operating at the TeV scale. The studies detailed within this thesis deal primarily with the development of Monolithic Active Pixel Sensors (MAPS) which could be used as the …
In this thesis we study the noise in Coulomb blockaded quantum dots in the vicinity of the peak of conductance in a full quantum treatment using the Keldysh technique. In previous work on this system, the emphasis have been on master equation approaches in the shot noise regime.…
The response of powder of the Nickel-based superalloy CM247LC to a range of Hot Isostatic Pressing (HIPping) conditions and post-HIP heat treatments has been investigated as a preliminary step in the assessment of net shape HIPping as a possible process-route for component produ…
Device scaling has resulted in large scale integrated, high performance, low-power, and low cost systems. However the move towards sub-100 nm technology nodes has increased variability in device characteristics due to large process variations. Variability has severe implications…
Many theories associated with quantum gravity, such as string theory, predict violations of inverse square law (ISL) of gravity at sub millimetre distances. To search for such experimental signatures we developed a magnetically levitated cryogenic torsion balance, the SSTB, and …
Einstein’s Theory of General Relativity describes gravity as the curvature of space-time and predicts gravitational waves. Laser interferometric gravitational wave detectors attempt to observe the strain gravitational waves exert on space-time, which is obscured by seismic, ther…
Hospital-acquired infections, a large proportion of which are derived from contact transmission, represent a massive global challenge. It has been proved that surface modification of biomaterials with Ag or Cu has evolved as a potentially effective method for preventing bacteria…
This thesis addresses two similar problems that combine the theory of Coulomb drag with the emerging field of graphene physics. First, the theory of Coulomb drag between two graphene mono-layers is extended to include finite temperature. It is found that the effect is strongly e…
A widely used analytical, image charge, model of the SNMM was analysed for the first time in terms of its ability to predict the response of the SNMM to both bulk and thin film dielectrics. For the first time it was shown that the uncertainty in fitting to the model reduces from…
The research questions posed for this work were as follows: Can speech recognition and techniques for topic spotting be used to identify spoken intent in unconstrained natural speech? Can gesture recognition systems based on statistical speech recognition techniques be used to b…