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…
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Design techniques used for two-port coupled resonator circuits are extended in this thesis to multi-port coupled resonator circuits. Three-port coupled resonator power dividers and diplexers are demonstrated in particular. The design approach is based on coupling matrix optimiza…
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…
In this thesis, a modal decomposition method and a time-frequency-domain formalism for the analysis of multimode dynamics of semiconductor ring laser are developed. The diffusion coefficient is suggested as a crucial parameter to take into account. The directional switching dyna…
Assessment of candidate materials for fusion power plants provide one of the major structural materials challenges of the next decades. Computer simulation provides a useful alternative to experiments on real-life irradiated materials. Within the framework of a multi-scale model…
This work is concerned with the design of sonar transducers operating in the frequency range 100 kHz to 1 MHz. The transducer frequency responses are predicted using a one-dimensional transmission line analysis. Differences between predicted and measured results are shown to be …
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…
This work describes the investigation of optical ring or disk micro-resonator as elements in label-free biosensing devices. The use of polymeric materials for micro-resonator structures recently has been gain major interest multi disciplinary research since it allows rapid and s…
Wind power is growing rapidly around the world as a means of dealing with the world energy shortage and associated environmental problems. Ambitious plans concerning renewable energy applications around European countries require a reliable yet economic system to generate, colle…
This research uses a SystemC design methodology to model and design complex wireless communication systems, because in the recent years, the complexity of wireless communication systems has increased and the modelling and design of such systems has become inefficient and challen…
Although the Fogel-Huang algorithm, utilised in ellipsoid parameter estimation, uses the unique minimum-volume (Behrend-Löwner/John - BLJ) ellipsoid containing the intersection of an ellipsoid and a strip, the ellipsoid resulting from an iteration of the FH algorithm to find an …
The objective of the work of this thesis is to design, fabricate, and characterise high performance micromachined antennas with fixed and reconfigurable bandwidth. The developed integrated antennas are suitable for MMICs integration at millimetre wave frequencies (G-band) on MMI…
The objective of this thesis was to develop a new methodology for the improvement of the interface properties of gold electrodes for neural implants. The goal was to increase the surface area without a change in geometrical footprint of the electrode with nano-fabrication tools.…
Recently, excellent properties have been realised from structures formed by carbon nanotubes. This propelled their use as nanoscale electronic devices in the information technology industry. The discovery of carbon nanotubes has stimulated interest in carbonbased electronics. Me…
Fullerene derivatives have been demonstrated as negative-tone resists for electron beam lithography with impressive capability for high resolution and high plasma etching resistance, due to their carbon-rich nature. Their primary drawback of extremely poor sensitivity has been a…
The differences between a musical score and an instance of that music in a performance, communicates a performer’s view of the information contained in that score. The main hypothesis in this thesis is that by measuring quantifiable parameters such as tempo, dynamics and motion f…
Over the past decades, the adoption of electronic systems for the manufacturing of automotive vehicles has been exponentially popularized. This growth has been driven by the premium automobile sector where, presently, diverse electronic systems are used. These electronic systems…
The arrival of cheap and fast microcomputers has stimulated the development of machine condition monitoring systems. Such systems measure one or more machine performance parameters, with a view to detecting the early signs of failure and initiating some form of action. To help d…
Silicon as a platform for photonics has recently seen a very large increase in interest because of its potential to overcome the bandwidth limitations of microprocessor interconnects and the low manufacturing cost given by the high compatibility with the already established micr…