Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Karol Lang. Vita. Includes bibliographical references.

Thesis (Ph.D.)--York University, 2003. Graduate Programme in Physics and Astronomy. / Typescript. Includes bibliographical references (leaves 124-126). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss &rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NQ99172

No description available.

D.Ing. / This thesis treats aspects of electromagnetic integration in planar structures. These structures are for use in power electronic converters. The electromagnetically integrated structures fulfil the same electromagnetic function as conventional component structures, but have manufacturing advantages. In order to reduce the cost of power electronic systems, a new cost effective manufacturing technology is needed. In this work a planar manufacturing approach is considered. This manufacturing approach lends itself well to the concept of integrated electromagnetics, where one physical structure fulfils more than one electromagnetic function. As not all the electromagnetic functions of a given converter may be integrated into a single structure, the approach is one of hybridisation. Some aspects remain conventional and some aspects are totally electromagnetically integrated. A proposal for a new schematic representation of converter topologies is put forward. These new schematics bridge the gap between conventional circuit diagrams and full three dimensional figures of the physical structures. These schematics form the basis of the design and analysis procedure and are necessary in order to convey information on the structures in a concise manner. A complex electromagnetic function, that of a resonant circuit with transformer coupling, is described and analysed in detail. The design equations governing the structure are derived and their implications on the volume of the structure is discussed. In the analysis only first order effects are considered. Two case studies are carried out. The two converters are described in detail with respect to their construction. Several aspects of general planar construction are identified and discussed.

No description available.

This investigation is an attempt to verify the original work done by George Antonoff and Anne Rowley, and to contribute specific data on the action of a magnetic field on aluminum cells. Experiments of the type they have described have been performed and an extensive set of data has been collected. It was thought that if the results of Antonoff and Rowley could be duplicated, further investigation would be warranted. However, the experiments have produced negative results. These results are described in detail in these chapters.

The electromagnetic interaction between antenna elements is referred to as mutual coupling. This phenomenon can cause undesirable effects in an antenna array such as distortion of the radiation pattern and loss of efficiency. This report models mutual coupling in a scattering parameter context and utilizes microwave network theory to establish a set of nonlinear simultaneous equations describing a compensation network. Iterative numerical techniques are then used to solve for the parameters of the compensation network. Three specific networks are investigated. Compensation examples are presented for two and eight element arrays. / M.S.

Neste trabalho estudamos, experimental e teoricamente, as flutuações de campos eletromagnéticos após a interação com sistemas atómicos em configuração de dois níveis com degenerescências. Estes sistemas atómicos eram preparados em superposições coerentes de seus estados obtidas através dos fenômenos de Transparência e Absorção Eletromagneticamente Induzidas. O sistema físico foi considerado em dois modelos teóricos semiclássicos distintos: resposta atómica linear e difusão de fase. Estes modelos se baseiam no fato de que lasers de díodo possuem excesso de ruído na fase, que durante o processo de interação coerente com o sistema atómico é transferido ressonantemente para o ruído de intensidade. Em nossa análise, observamos resultados não triviais em relação aos sinais de ruído e correlação entre os campos medidos. Verificamos que, num vapor atómico, a largura Doppler associada à transição tem um papel fundamental na composição elo sinal ele ruído. Observamos que mesmo transições que, a priori, estariam não ressonante podem ter contribuição significativa para o sinal ele ruído. Os modelos teóricos desenvolvidos apresentaram um bom acordo qualitativo com parte dos dados experimentais e se mostraram uma ferramenta útil para a análise da influência dos efeitos coerentes nas flutuações elos campos, quando o laser possui excesso de ruído ele fase. / We present a theoretical and experimental investigation of the fluctuations of electromagnetic fields after the interaction with degenerate two-level atomic systems. These atomic systems were prepared in coherent superpositions of the states obtained through Electromagnetically Induced Transparency (EIT) and Absorption (EIA). The physical system was studied in two semi-classical models: linear atomic response and phase diffusion. These models are based on the fact that diode lasers have excess phase noise, which in the interaction process is transferred to intensity noise. We observed non trivial results about the noise signals and the correlations between the fields. We showed that, in atomic vapor, the Doppler width has a fundamental role in the origin of the noise signal. The theoretical models show good qualitative agreement with part of the experimental result features and are a powerful tool to analyze field fluctuations, when the laser has excess phase noise.

Casimir forces originating from vacuum fluctuations of the electromagnetic fields are of increasing importance in many scientific and technological areas. The manifestations of these long-range forces at the nanoscale have led to the need of better understanding of their contribution in relation to the stability of different physical systems as well as the operation of various technological components and devices. This dissertation presents mathematical and theoretical methods to calculate the Casimir interaction in various infinitely long cylindrical nanostructures. A dielectric-diamagnetic cylindrical layer immersed in a medium is first considered. The layer has a finite thickness characterized with specific dielectric and magnetic properties. Another system considered is that of perfectly conducting concentric cylindrical shells immersed in a medium. The electromagnetic energy between two infinitely long straight parallel dielectric-diamagnetic cylinders immersed in a medium is also considered. The mode summation method is used to calculate the Casimir energy of all these systems. The energy dependence on the cylindrical radial curvature and dielectric response of the cylinders is investigated. The fundamental effects of these long range interactions are studied in the form of exciton-plasmon interactions in carbon nanotubes and this is achieved by looking at the dielectric response of carbon nanotubes.

As the complexity of interconnects and packages increases and the rise and fall time of the signal decreases, the electromagnetic effects of distributed passive devices are becoming an important factor in determining the performance of gigahertz systems. The electromagnetic behavior extracted using an electromagnetic simulation or from measurements is available as frequency dependent data. This information can be represented as a black box called a macromodel, which captures the behavior of the passive structure at the input/output ports. In this dissertation, the macromodels have been categorized as scalable, passive and broadband macromodels. The scalable macromodels for building design libraries of passive devices have been constructed using multidimensional rational functions, orthogonal polynomials and selective sampling. The passive macromodels for time-domain simulation have been constructed using filter theory and multiport passivity formulae. The broadband macromodels for high-speed simulation have been constructed using band division, selector, subband reordering, subband dilation and pole replacement. An automated construction method has been developed. The construction time of the multiport macromodel has been reduced. A method for reducing the order of the macromodel has been developed. The efficiency of the methods was demonstrated through embedded passive devices, known transfer functions and distributed interconnect networks.