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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.
81

Nanophotonic Silicon Electro-Optic Switch

Simili, Deepak 27 August 2012 (has links)
The design procedure for ultrafast silicon electro-optic switches using photonic crystals in order optimize the operation of the electro-optic switch is presented. The material medium selected for propagation of the optical signal through the switch is silicon nanocrystals in silica. A patterned slot waveguide with one-dimensional photonic crystals is proposed as the preferred slow light waveguide to be used in the design of the electro-optic switch. The ultrafast quadratic electro-optic Kerr effect is the physical effect utilized, and its analysis for slot waveguides is discussed. The optical structure analysis of the electro-optic switch using a ring resonator is presented and it is shown that the use of a slow light waveguide in the ring resonator can reduce the required externally applied electric field and the radius of the ring resonator.
82

Engineering optical nanomaterials using glancing angle deposition

Hawkeye, Matthew Martin Unknown Date
No description available.
83

Development of photonic crystal display devices

Krabbe, Joshua Dirk Unknown Date
No description available.
84

Hybrid photonic crystal nanobeam cavities: design, fabrication and analysis

Mukherjee, Ishita 07 1900 (has links)
Photonic cavities are able to confine light to a volume of the order of wavelength of light and this ability can be described in terms of the cavity’s quality factor, which in turn, is proportional to the confinement time in units of optical period. This property of the photonic cavities have been found to be very useful in cavity quantum electrodynamics, for e.g., controlling emission from strongly coupled single photon sources like quantum dots. The smallest possible mode volume attainable by a dielectric cavity, however, poses a limit to the degree of coupling and therefore to the Purcell effect. As metal nanoparticles with plasmonic properties can have mode volumes far below the diffraction limit of light, these can be used to achieve stronger coupling, but the lossy nature of the metals can result in extremely poor quality factors. Hence a hybrid approach, where a high-quality dielectric cavity is combined with a low-quality metal nanoparticle, is being actively pursued. Such structures have been shown to have the potential to preserve the best of both worlds. This thesis describes the design, fabrication and characterization of hybrid plasmonic – photonic nanobeam cavities. Experimentally, we were able to achieve a quality factor of 1200 with the hybrid approach, which suggests that the results are promising for future single photon emission studies. It was found that modeling the behaviour (resonant frequencies, quality factors) of these hybrid cavities with conventional computation methods like FDTD can be tedious, for e.g., a comprehensive study of the electromagnetic fields inside a hybrid photonic nanobeam cavity has been found to take up to 48 hours with FDTD. Hence, we also present an alternate method of analysis using perturbation theory, showing good agreement with FDTD. / Graduate
85

Wavelength conversion using reconfigurable photonic crystal MEMS/NEMS structures

Akdemir, Kahraman Daglar. January 2007 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: FDTD; Linear interpolation; MEMS; NEMS; Photonic crystals; Wavelength conversion; Frequency conversion; Doppler. Includes bibliographical references (leaves 107-114).
86

Development of fabrication processes for Si and GaN photonic crystal structures

Yeldandi, Satish. January 2008 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xi, 99 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 80-83).
87

Microresonators for organic semiconductor and fluidic lasers /

Vasdekis, Andreas E. January 2007 (has links)
Thesis (Ph.D.) - University of St Andrews, August 2007.
88

Polarity inverted GaN for photonic crystal biosensors

Tompkins, Randy P. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains xii, 142 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 138-142).
89

Thin-film photonic crystal LEDs with enhanced directionality /

Bergenek, Krister. January 2009 (has links)
Thesis (Ph.D.) - University of St Andrews, November 2009. / Restricted until 2nd November 2011.
90

Projetos de camadas fotônicas 2D e fabricação utilizando múltiplas exposições holográficas / Design of 2D photonic layers and fabrication using multiple holographic exposures

Menezes, Jacson Weber de 28 July 2006 (has links)
Orientador: Lucia Helena Deliesposte Cescato / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin / Made available in DSpace on 2018-08-08T11:13:35Z (GMT). No. of bitstreams: 1 Menezes_JacsonWeberde_M.pdf: 5177344 bytes, checksum: 63bfde864e58f6813890fced4db8f389 (MD5) Previous issue date: 2006 / Resumo: Nesta dissertação foi desenvolvido um novo método de gravação de estruturas bidimensionais em fotorresina, baseado na superposição de três exposições holográficas. Utilizando esta técnica, foi possível gravar estruturas de seção transversal circular. Isso resolve o problema da redução da área do gap fotonico que ocorre com as estruturas cilíndricas de seção transversal elíptica, obtida quando são utilizadas apenas duas exposições. Controlando-se a fase entre a terceira exposição e as duas anteriores é possível também gerar padrões hexagonais com diferentes formas de cilindros, que correspondem aos "átomos" do cristal fotonico, que podem apresentar novas propriedades fotonicas. Para projetar cristais fotonicos que apresentam gap fotonico na região de interesse do espectro eletromagnético, foi utilizado um programa baseado no método dos elementos finitos. Nestes projetos foram consideradas as dimensões e formas que podem ser fabricadas utilizando a técnica de dupla exposição holográfica assim como foi utilizada a aproximação de índice de refração equivalente para levar em conta a espessura da camada fotonica. Utilizando a superposição de duas exposições holográficas, associadas à litografia por corrosão por íon reativo, foram feitas tentativas de fabricação das camadas fotonicas projetadas em três materiais diferentes: silício policristalino, silício amorfo hidrogenado e silício cristalino / Abstract: In this work, it was developed a new recording method of the 2D structures in photoresist, based on the superimposition of three holographic expositions. This technique solves the problem of asymmetry of hexagonal structures, arising from the superimposition of only two expositions, which causes a strong reduction of the photonic band gap area. By controlling the phase-shift between the third exposition and the former two exposures, it is possible to generate new hexagonal patterns that can present different properties. In the design of the 2D photonic layers that present Photonic Band Gaps in the near infra-red region of the electromagnetic spectrum, it was used a software based on finite elements method. To consider the thickness of the photonic layer it was used the approach of equivalent refractive index. In the design we take into account the dimensions and shapes that can be fabricated using the technique of holographic lithography associated with RIE (Reactive Ion Etching). For fabrication of the structures we used double holographic exposures followed by RIE lithography in three different materials: poly-silicon, amorphous silicon and crystalline silicon / Mestrado / Física da Matéria Condensada / Mestre em Física

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