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dc.contributor.advisor Yoshie, Tomoyuki en_US
dc.contributor.author Tang, Lingling en_US
dc.date.accessioned 2011-01-05T14:40:06Z
dc.date.available 2011-01-05T14:40:06Z
dc.date.issued 2010 en_US
dc.identifier.uri http://hdl.handle.net/10161/2980
dc.description Dissertation en_US
dc.description.abstract <p>The objective of this dissertation work is to examine light localization in semiconductors provided by a complete photonic bandgap via three-dimensional (3D) woodpile photonic crystals. A 3D photonic crystal is a periodic nanostructure that demonstrates omni-directional Bragg reflection. These materials are anticipated to become a powerful tool for engineering light propagation and localization within subwavelength scales due to their complete photonic bandgap and the distinctive dispersion relation. </p><p>The approach of realizing microcavities in this dissertation is to combine multi-directional etching fabrication methods with mode gap design. Modulation of unit cell size along a line-defect 3D waveguide could bring a guiding mode into the mode gap region of the waveguide and form a microcavity with a resonance inside the complete photonic bandgap. The designed microcavities could be fabricated by multi-directional etching methods because they can structurally be decomposed into two sets of connected and straight dielectric rods. </p><p>Ultra-high-quality factor microcavities and sub-wavelength-scale waveguides are designed without introduction of local disorders. Monopole, dipole, and quadrupole resonant modes are demonstrated with a small modal volume. The smallest modal volumes obtained are 0.36 cubic half-wavelengths for a resonance field in vacuum, and 2.88 cubic half-wavelengths for a resonance field in a dielectric. Direct metal contacts with the microcavities do not significantly deteriorate the quality factors because the resonant fields are located inside the microcavities. Single-mode woodpile waveguides are also designed in both lateral and vertical propagation directions. </p><p>The multi-directional etching method is a simple approach to the fabrication of woodpile photonic crystals and designed optical components with a variety of crystal orientations and surfaces, including (110), (001), (100), and (010) planes. An arbitrary surface plane (mn0) is obtained with this method, where m and n are integers. Moreover, it can also produce large area woodpile photonic crystals with high precision in silicon and GaAs materials.</p><p>These optical components in woodpile photonic crystals would be building blocks of high-density, low-loss 3D integrated optics, cavity quantum electrodynamics (QED), nonlinear optics, and enable the realization of current-injection optical devices.</p> en_US
dc.subject Engineering, Electronics and Electrical en_US
dc.subject Light localization en_US
dc.subject Microcavity en_US
dc.subject Nanofabrication en_US
dc.subject Photonic bandgap en_US
dc.subject Photonic crystal en_US
dc.subject Waveguide en_US
dc.title Subwavelength-scale Light Localization in Complete Photonic Bandgap Materials en_US
dc.type Dissertation en_US
dc.department Electrical and Computer Engineering en_US

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