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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.
1

Design of metamaterials with broad-band optical properties. / 光學闊頻超材料設計 / CUHK electronic theses & dissertations collection / Design of metamaterials with broad-band optical properties. / Guang xue kuo pin chao cai liao she ji

January 2013 (has links)
Lee, Hon Ping = 光學闊頻超材料設計 / 李翰屏. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 79-81). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Lee, Hon Ping = Guang xue kuo pin chao cai liao she ji / Li Hanpin.
2

Instruments for measuring properties of infrared transmitting optical materials

Platt, Benjamin Curtis, 1942- January 1976 (has links)
No description available.
3

Structural studies of organic and organometallic compounds using X-ray and neutron techniques

Cole, Jacqueline M. January 1997 (has links)
This thesis is sub-divided into two parts. Part (i) is entitled 'Structure / Property Relationships in Non-linear Optical Materials' (chapters 1-8) whilst part (ii) is entitled 'Structural Studies of imido, (bis)imido and aryloxide group VA and VIA transition metal complexes' (chapters 9-10).Chapters 1, 2 and 3 provide an introduction to non-linear optics, X-ray and neutron experimental techniques used in this thesis and charge density studies respectively. Chapters 4 to 8 describe the investigations of the part (i) topic. These include bond length alternation studies on a series of tetracyanoquinodimethane derivatives and a charge density study of one of these compounds in chapter 4. Several other charge density studies are reported in chapters 5 and 6 which concentrate on methyl- nitropyridine and nitroaniline derivatives and the compound, 3-( 1,1 -dicyanoethenyl)-l-phenyl-4,5- dihydro-1 H-pyrazole (DCNP) respectively. Chapter 5 also deals with the effect of intermolecular interactions on the non-linear optical phenomenon whilst in chapter 6, a detailed analysis of the thermal motion present in DCNP is also given. Investigations on intermolecular interactions are also reported in chapters 7 and 8 which studies the compounds, N-methylurea and zinc(tris)thiourea sulphate respectively. In the former case, the neutron derived structure of N-methylurea is reported at two temperatures and it is revealed that disorder is present at the higher temperature. In the latter case, neutron results from an instrument presently in the testing stages of its development are reported and contrasted with those obtained using a well established instrument. Chapters 9 and 10 describe the investigations of the part (ii) topic. These concentrate on the structural features of two series of organometallic compounds which have potential use as polymerization catalysts. Relationships between structure and reactivity are reported.
4

UV-Ozone Oxide Treatments for High-Efficiency Silicon Photovoltaic Devices

Gao, Munan 01 January 2021 (has links) (PDF)
Fabrication of solar cells with higher efficiency, simpler processes and lower cost is largely perceived as the ultimate goal for photovoltaic research. To reach such a goal each step needs to be refined and optimized. In this dissertation, a UV-ozone treatment is proposed as a simple and versatile process that can be applied to multiple fabrication steps for improvement. The UV-ozone cleaning method provides comparable surface cleaning quality to more expensive and hazardous industrial standard RCA clean with less chemical used. A good passivation quality was achieved on both n-type and p-type silicon wafer by a silicon oxide/aluminum oxide passivation stack, formed by UV-ozone treatment and ALD. Creating a thin layer of silicon oxide on the silicon wafer surface before depositing the aluminum contact form a metal-insulator-semiconductor (MIS) contact structure, showing low contact resistance for both n-type and p-type wafers. Device performance simulation was performed by Quokka and Sunsolve using experimental results. The simulation results shown promising power conversion efficiency and indicated contact resistance as the key factor in reaching higher efficiency.
5

FORMATION OF SILICON NANOCRYSTALS IN SiO2 BY SILICON IMPLANTATION AND SUBSEQUENT ANNEALING

IBNA, SHAIKH MD ASKER 04 1900 (has links)
<p>Since the first description of Si nanocrystals, research in this field has gone through raid progress and potential applications of Si nanocrystals have been established. There are several methods applicable to the fabrication of Si nanocrystals with one of the most used being ion implantation followed by thermal annealing. Two types of thermal annealing are available for use: furnace annealing (FA) for several hours, normally in an N<sub>2</sub> atmosphere; and rapid thermal annealing (RTA) for a short time (less than a few minutes), again in an inert atmosphere such as N<sub>2</sub>. The formation of the nanocrystals then proceeds with decomposition, segregation, diffusion, nucleation, aggregation, growth and crystallization. This formation requires temperatures in excess of 1000<sup>o</sup> C such that noticeable photoluminescence may be observed. This thesis explores the fabrication of Si nanocrystals using the McMaster ion implanter and subsequent RTA. The implantation conditions required to form luminescent nanocrystals are determined. For example, for an implantation energy of 10 KeV a minimum dose of 1.5 10<sup>16</sup> ions cm<sup>-2</sup> is required. The relationship between luminescent intensity and post-implantation annealing is also explored. An optimum annealing temperature of 1100<sup>o</sup>C is found. For the first time to the author’s knowledge, a study of the effects of thin film thickness on luminescent intensity is conducted. The major conclusions of this thesis are i) a specific thickness of oxide layer has the maximum PL for a fixed implantation energy and implantation dose, ii) PL intensity is inversely proportional with measuring temperature., iii) the type of oxidation process has a large effect on PL intensity.</p> / Master of Applied Science (MASc)
6

The development and use of refractometer for measuring optical cements in the infrared

Korniski, Ronald James, 1949- January 1975 (has links)
No description available.
7

Laser damage studies in the ultra-violet

Wiseall, Stephen S. January 1989 (has links)
The work in this thesis is a study of excimer laser induced damage in optical materials. This includes characterization of the focused laser radiation, development of sensitive techniques for the early detection of laser damage and finally laser damage studies at 193 nm and 248 nm in crystalline materials, metal mirrors and dielectric coatings. Characterization of the focused laser radiation involved pulse energy, temporal pulse profile and spatial profile measurements. This was assisted by development of a laser attenuator using a variable length liquid cell with a dynamic range of 25 dB. Non-linear absorption phenomena were observed in liquids at high intensities. Beam profiling methods were used to show the intensity distribution in the focal region of a lens was reproducible and approximated to a 2-D Gaussian function [continued]…
8

Synthesis and stability studies of Z-beta-(1-substituted-4-pyridinium)-alpha-cyano-4-styryldicyanomethanide nonlinear optical chromophores /

Weir, Cara A. M. January 1900 (has links)
Thesis (M. Sc.)--Carleton University, 2003. / Includes bibliographical references. Also available in electronic format on the Internet.
9

The optical spread functions and noise characteristics of selected paper substrates measured in typical reflection optical system configurations /

Kofender, Janet L. January 1987 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1987. / Typescript. Includes bibliographical references (leaves 124-128).
10

Light emission from silicon /

Seiferth, Frederick J. January 1994 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1994. / Typescript. Includes bibliographical references.

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