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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Distributed feedback zirconia and zirconia-ORMOSIL waveguide lasers.

January 2003 (has links)
Wang Jun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 74-79). / Abstracts in English and Chinese. / Acknowledgements --- p.i / List of publications --- p.ii / Abstract (In English) --- p.iii / Abstract (In Chinese) --- p.v / Table of contents --- p.vii / List of figures --- p.x / List of tables --- p.xiv / Chapter Chapter I --- Introduction --- p.1 / Chapter Chapter II --- Dye-doped sol-gel zirconia and zirconia-organically modified silicate waveguides --- p.6 / Chapter 2.1 --- General sol-gel process --- p.6 / Chapter 2.2 --- Dye-doped sol-gel zirconia and zirconia-ORMOSIL waveguides --- p.7 / Chapter Chapter III --- Basic theory and experiment setup of distributed feedback waveguide lasers --- p.13 / Chapter 3.1 --- Coupled-wave theory of distributed feedback lasers --- p.13 / Chapter 3.2 --- Introduction on the theory of planar optical waveguide --- p.16 / Chapter 3.3 --- Experiment setup design of DFB waveguide lasers --- p.19 / Chapter Chapter IV --- Zirconia and zirconia-organically modified silicate distributed feedback waveguide lasers tunable in the visible --- p.23 / Chapter Chapter V --- Tunable multi-wavelength distributed feedback zirconia waveguide lasers --- p.35 / Chapter 5.1 --- Brief introduction on multi-wavelength lasers --- p.35 / Chapter 5.2 --- R6G-doped zirconia multi-mode waveguides --- p.36 / Chapter 5.3 --- Experimental results and discussion --- p.39 / Chapter 5.3.1. --- Dual- and quadruple-wavelength DFB waveguide lasers --- p.39 / Chapter 5.3.2. --- The dispersion characteristics of multi-wavelength DFB waveguide lasers --- p.44 / Chapter 5.3.3. --- Determination of waveguide parameters by the DFB technique --- p.48 / Chapter 5.4 --- Summary --- p.51 / Chapter Chapter VI --- Distributed feedback laser action in sol-gel glass symmetric waveguides --- p.53 / Chapter 6.1 --- The fabrication of dye-doped glass symmetric waveguides --- p.54 / Chapter 6.2 --- Experimental results and discussion --- p.56 / Chapter 6.2.1. --- DFB laser action in sol-gel glass symmetric-asymmetric waveguide --- p.56 / Chapter 6.2.2. --- Dispersion characteristics of DFB symmetric and asymmetric waveguide lasers --- p.61 / Chapter 6.3 --- Summary --- p.65 / Chapter Chapter VII --- Summary --- p.69 / References --- p.74
122

Finite element modeling of dielectric waveguides

Vishakhadatta, Gannavaram D. 01 April 1993 (has links)
Dielectric waveguides are becoming important for their numerous applications in integrated optics. The study of dielectric waveguides by analytical techniques is not sufficient for many variations in waveguide shape, anisotropy, and inhomogeneity commonly encountered in waveguide materials. This work studies the finite element method as an accurate tool for the numerical modeling of dielectric waveguides. Other commonly used numerical techniques are also considered. The implementation of the finite element method is discussed. The finite element technique is also modified to incorporate the lack of fixed-potential boundary conditions in dielectric waveguides. The results of the simulations are documented for several experimental and analytical test cases. Measurements were made on waveguides fabricated in-house using the plasma-enhanced chemical vapor deposition (PECVD) films of silicon oxynitride. The light source was a 6328 A helium-neon laser. The results of the finite element simulations are compared with the experimental results and with other previously documented numerical and analytical results from the literature. The finite element method developed here is shown to be in good agreement with these results and will be useful in solving for the modes of novel waveguide designs. / Graduation date: 1993
123

Integration of thin film GaAs MSM photodetector in fully embedded board-level optoelectronic interconnects

Lin, Lei 28 August 2008 (has links)
Not available / text
124

Highly integrated polymer photonic switching and interconnects

Wang, Xiaolong 28 August 2008 (has links)
Not available / text
125

NONLINEAR OPTICAL PHASE CONJUGATION BY 3-WAVE AND 4-WAVE MIXING

Tomita, A. (Akira) January 1980 (has links)
No description available.
126

The application of Trefftz-FLAME to electromagnetic wave problems /

Pinheiro, Helder Fleury, 1967- January 2008 (has links)
Numerical analysis of the electromagnetic fields in large, complex structures is very challenging due to the high computational overhead. Recently, it has been shown that a new method called Trefftz-FLAME ( Flexible Local Approximation MEthod) is suitable for problems where there exist a large number of similar structures. / This thesis develops Trefftz-FLAME in two areas. First, a novel 2D Trefftz-FLAME method incorporates the modal analysis and port boundary condition that are essential to an accurate calculation of reflection and transmission coefficients for photonic crystal devices. The new technique outperforms existing methods in both accuracy and computational cost. / The second area pertains to the 3D, vector problem of electromagnetic wave scattering by aggregates of identical dielectric particles. A methodology for the development of local basis functions is introduced, applicable to particles of any shape and composition. Boundary conditions on the surface of the finite FLAME domain are described, capable of representing the incident wave and absorbing the outgoing radiation. A series of problems involving dielectric spheres is solved to validate the new method. Comparison with exact solutions is possible in some cases and shows that the method is able to produce accurate near-field results even when the computational grid spacing is equal to the radius of the spheres.
127

Characterizations and design of planar optical waveguides and directional couplers by two-step K+ -Na+ ion-exchange in glass

Albert, Jacques January 1987 (has links)
Planar optical waveguides fabricated by K$ sp+$-Na$ sp+$ ion-exchange in soda-lime glass substrates are investigated. / Experimental characterizations of planar waveguide with respect to a wide range of fabrication conditions have been carried out, including detailed measurements of the refractive index anisotropy resulting from the large induced surface stresses. / Parallel to this, the non-linear diffusion process of ion-exchange was simulated numerically to provide, along with the results of the characterizations, a complete description of the refractive index profile from any set of fabrication conditions. / The magnitude of the maximum surface index change observed was shown theoretically to be almost entirely due to the induced stress at the surface of the substrate, arising from the presence of the larger potassium ions. / Finally, a novel class of single-mode channel waveguides, made by a "two-step" ion-exchange was analyzed. A simple model for these waveguides was developed and used in the design of two directional coupler structures which were fabricated and measured. / The two-step process was conceived because it relaxes waveguides' dimensional control, yielding single-mode guides of larger size, better suited for low-loss connections to optical fibers. It also provides an additional degree of freedom to adjust device properties.
128

Lightpath topology configuration for wavelength-routed IP/MPLS networks in a multi-layered environment integrated models, algorithms, and analysis /

Agrawal, Gaurav, Medhi, Deepankar. January 2007 (has links)
Thesis (Ph. D.)--School of Computing and Engineering. University of Missouri--Kansas City, 2007. / "A dissertation in computer networking and telecommunication networking." Advisor: Deep Medhi. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Jan. 24, 2008. Includes bibliographical references (leaves 130-138). Online version of the print edition.
129

Analysis of linear and nonlinear coupled dielectric waveguides /

Chang, Hosung. January 1993 (has links)
Thesis (Ph. D.)--Oregon State University, 1993. / Typescript (photocopy). Includes bibliographical references (leaves 102-110). Also available on the World Wide Web.
130

Stress engineering for polarization control in silicon-on-insulator waveguides and its applications in novel passive polarization splitters/filters /

Ye, Winnie Ning. January 1900 (has links)
Thesis (Ph.D.) - Carleton University, 2007. / Includes bibliographical references (p. 194-201). Also available in electronic format on the Internet.

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