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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.
21

VCSEL characterisation for use in optical interconnects /

O'Brien, Christopher John. January 2006 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2006. / Includes bibliography.
22

Characterization of the surface plasmon modes in planar metal-insulator-metal waveguides by an attenuated total reflection approach

Lin, Chien-I 30 September 2011 (has links)
Surface plasmons are of interest for various applications, including optical interconnects and devices, light sources, nanolithography, biosensors, solar cells, and negative-refraction prisms or superlenses. Some of the most important applications are SP-based optical interconnects and devices, which offer the potential of realizing integrated optical nanocircuitry due to the subwavelength confinement and the slow-wave nature of SPs. The fundamental building element of these applications is the plasmonic waveguide. Among the family of various plasmonic waveguides, the metal-insulator-metal waveguide has superior lateral confinement because of the relatively shallow field penetration into the metal claddings (about a skin depth -- usually tens of nanometers). Such subwavelength confinement cannot be achieved by conventional dielectric optical waveguides. However, the loss in the MIM waveguide is substantial due to the strong absorption of metal in the visible or near-infrared spectrum. Therefore, the design, simulation, and measurement of the loss in the MIM waveguide are critically important in the development of SP-based nanocircuitry. Surface plasmons (SPs) are of interest for various applications, including optical interconnects and devices, light sources, nanolithography, biosensors, solar cells, and negative-refraction prisms or superlenses. Some of the most important applications are SP-based optical interconnects and devices, which offer the potential of realizing integrated optical nanocircuitry due to the subwavelength confinement and the slow-wave nature of SPs. The fundamental building element of these applications is the plasmonic waveguide. Among the family of various plasmonic waveguides, the metal-insulator-metal (MIM) waveguide has superior lateral confinement because of the relatively shallow field penetration into the metal claddings (about a skin depth -- usually tens of nanometers). Such subwavelength confinement cannot be achieved by conventional dielectric optical waveguides. However, the loss in the MIM waveguide is substantial due to the strong absorption of metal in the visible or near-infrared spectrum. Therefore, the design, simulation, and measurement of the loss in the MIM waveguide are critically important in the development of SP-based nanocircuitry. Owing to the subwavelength sizes of MIM waveguides, the excitation of an MIM plasmonic mode typically requires end-fire coupling with tapered fibers or waveguides. Further, the conventional loss measurements require the usage of a near-field scanning optical microscopy (NSOM) or multiple waveguide samples with various length scales; however, the two aforementioned techniques are both complicated and have issues of sensitivity to uncontrollable environmental factors or variations in coupling strength, respectively. These experimental challenges have been a primary reason for the slow experimental development of the MIM waveguide and device. The research in this thesis focuses on the development of the transverse transmission/reflection (TTR) method, which is a more reliable, accurate, and straightforward method of characterizing the plasmonic modes in the MIM waveguide. The theory of the TTR method, which incorporates an attenuated total reflection (ATR) configuration, is developed based on the transmission matrix formulation. A methodology for obtaining the propagation constant and attenuation coefficient of a plasmonic mode in an MIM waveguide is illustrated. Using the Metricon Prism Coupler, the TTR method is experimentally applied to planar, single-mode MIM (Au-SiO$_2$-Au) waveguides with various core thicknesses at $lambda=1550$ nm. The experimental results are in very good agreement with the theoretical results. It is also shown experimentally that the TTR method is robust against difficult-to-quantify parameters such as the metal cladding thickness and the air gap thickness between the prism and the waveguide. As a result, the TTR method can be readily applied by using other similar ATR or prism-coupler configurations, without concern for the sensitivity issues caused by the subtle differences between various configurations. Moreover, the TTR method is also experimentally applied to planar, multimode MIM waveguides. Multimode MIM waveguides, which have larger core sizes, may be of interest for applications in low-loss interconnects or tapered end-couplers. Thanks to the superior angular selectivity of the ATR configuration, the TTR method is capable of detecting the propagation constant and attenuation coefficient of each mode. To the best of the author's knowledge, this is the first time the propagation constant of each mode in a multimode MIM waveguide has been individually measured. Also, to the best of the author's knowledge, this is the first time the attenuation coefficient of each mode in a multimode MIM waveguide has been individually measured. The TTR method is proved to be a reliable, accurate, and straightforward approach to characterize plasmonic modes in MIM waveguides. Future research will target the extension of the TTR method to 2D MIM waveguides, asymmetric MIM waveguides, and inclusion of scattering loss. Taking full advantage of the TTR method, the development of plasmonic devices can be potentially accelerated. The theory of the TTR method, which incorporates an attenuated total reflection (ATR) configuration, is developed based on the transmission matrix formulation. A methodology for obtaining the propagation constant and attenuation coefficient of a plasmonic mode in an MIM waveguide is illustrated. Using the Metricon Prism Coupler, the TTR method is experimentally applied to planar, single-mode MIM (Au-SiO$_2$-Au) waveguides with various core thicknesses at $lambda=1550$ nm. The experimental results are in very good agreement with the theoretical results. It is also shown experimentally that the TTR method is robust against difficult-to-quantify parameters such as the metal cladding thickness and the air gap thickness between the prism and the waveguide. As a result, the TTR method can be readily applied by using other similar ATR or prism-coupler configurations, without concern for the sensitivity issues caused by the subtle differences between various configurations. Moreover, the TTR method is also experimentally applied to planar, multimode MIM waveguides. Multimode MIM waveguides, which have larger core sizes, may be of interest for applications in low-loss interconnects or tapered end-couplers. Thanks to the superior angular selectivity of the ATR configuration, the TTR method is capable of detecting the propagation constant and attenuation coefficient of each mode. To the best of the author's knowledge, this is the first time the propagation constant of each mode in a multimode MIM waveguide has been individually measured. Also, to the best of the author's knowledge, this is the first time the attenuation coefficient of each mode in a multimode MIM waveguide has been individually measured. The TTR method is proved to be a reliable, accurate, and straightforward approach to characterize plasmonic modes in MIM waveguides. Future research will target the extension of the TTR method to 2D MIM waveguides, asymmetric MIM waveguides, and inclusion of scattering loss. Taking full advantage of the TTR method, the development of plasmonic devices can be potentially accelerated.
23

Broad-band and scalable circuit-level model of MSM PD for co-design with preamplifier in front-end receiver applications

Cha, Cheolung. January 2004 (has links) (PDF)
Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2004. / Rhodes, William, Committee Member ; Brooke, Martin, Committee Chair ; Chang, G.K., Committee Member ; Hasler, Paul, Committee Member ; Kohl, Paul, Committee Member. Includes bibliographical references (leaves 133-139).
24

Optical clock signal distribution and packaging optimization

Wu, Linghui. January 2002 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
25

Centralized optical backplane bus using holographic optical elements for high performance computing

Bi, Hai, 1975- 28 August 2008 (has links)
Optical communication is distinguished for its enormous interconnect capacity over long distance. As the cost of optical components drops, high bandwidth optical systems were successfully employed into local area network and computer racks because electrical counterparts are not able to deal with the data rate demands for these applications. With the popularity of multi-core CPU in High Performance Computers, the board-to-board interconnects exclusive based on electrical technology in backplane applications become insufficient because of not only bandwidth crises, but also wiring congestions. Many researches have projected that the progress of optical technology will further push down the boundary demarcating electrical and optical domains in the interconnect hierarchy. Accordingly, backplane or even board-to-board level interconnects will benefit from the complement of optical interconnect. From architecture point of view, an optical bus implementation of the optical interconnect has the potential advantage of both huge bandwidth and elimination of wiring congestion. In contrast, optical waveguide and free-space interconnects although provide high bandwidth capacity, are essentially point-to-point technology which requires routing to a central switch on the backplane. The centralized approach that was based on substrate guided optical interconnects is the only way known that fulfills a uniform fan-out for different nodes in a bus architecture, which allows medium sharing among nodes. In this dissertation, innovative bit-interleaved optical backplane bus architecture is created based on centralized substrate-guide optical interconnect, which allows the tremendous bandwidth capacity to be shared by retaining the share bus architecture. Therefore, a secure and reliable high speed transmission channel could be established by distributing copies of confidential information separately. The feature provided by this innovative design cannot be fulfilled using electrical interconnects or other optical point-to-point technology without causing wiring congestions. In this dissertation, the optical characteristics of the centralized optical bus such as bandwidth and alignment tolerance are analyzed so that multi-channel implementation are successful on the fabricated optical interconnect layer. A 3-board-16-channel computer server using optical backplane board demonstrator using centralized optical bus was built upon the simulation, design and packaging work.
26

Optical clock signal distribution and packaging optimization

Wu, Linghui 09 May 2011 (has links)
Not available / text
27

Multimode polymer waveguides for high-speed on-board optical interconnects

Bamiedakis, Nikolaos January 2009 (has links)
No description available.
28

Elements of an applications-driven optical interconnect technology modeling framework for ultracompact massively parallel processing systems

Cruz-Rivera, Jose L. 05 1900 (has links)
No description available.
29

Bandwidth efficient modulation techniques for lightwave systems

Lanka, Sivakumar. January 2008 (has links)
Thesis (Ph. D.)--University of Nevada, Reno, 2008. / "August, 2008." Includes bibliographical references (leaves 118-125). Online version available on the World Wide Web.
30

Proof of feasibility of a free-space optical cross-connect system using digital mems

Argueta Díaz, Victor, January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xvii, 176 p.; also includes graphics (some col.). Includes bibliographical references (p. 171-176). Available online via OhioLINK's ETD Center

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