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Guided-Wave Superconducting Quantum Optoelectronic Devices

This thesis investigates a novel optoelectronic platform based on
the integration of superconductive structures, such as thin films
and micro-constrictions, with optical waveguides for ultra-fast and
ultra-sensitive devices with applications including high-speed
optical communications, quantum optical information processing, and
terahertz (THz) devices and systems.

The kinetic-inductive photoresponse of superconducting thin films
will be studied as the basic optoelectronic process underlying the
operation of these novel devices. Analytical formulation for the
non-bolometric response is presented, and experimental
photodetection in YBCO meander-line structures will be demonstrated.

A set of superconducting coplanar waveguides (CPW) are designed and
characterized, which support the operation of the devices at
microwave frequencies. Microwave-photonic devices comprising a
microwave transmission line and a light-sensitive element, such as a
meander-line structure, are designed and measured for implementation
of optically tunable microwave components.

In order to support low-loss and low-dispersion propagation of
millimeter-wave and THz signals in ultra-fast and wideband
kinetic-inductive devices, surface-wave transmission lines are
proposed, incorporating long-wavelength Surface Plasmon Polariton
(SPP) modes in planar metal-dielectric waveguides.

The theory of superconducting optical waveguides, including
analytical formulation and numerical methods, is developed in
detail. The implementation of superconducting optical waveguides is
discussed thoroughly, employing conventional dielectric-waveguide
techniques as well as optical SPP modes.

Superconductive traveling-wave photodetectors (STWPDs) are
introduced as a viable means for ultra-fast and ultra-sensitive
photodetection and photomixing. A modified transmission line
formalism is developed to model STWPDs, where light is guided
through an optical waveguide and photodetection is distributed along
a transmission line.

As an appendix, a systematic approach is developed for the analysis
of carrier transport through superconducting heterostructures and
micro-constrictions within the Bogoliubov-de Gennes (BdG) framework.
The method is applied to study the role of Andreev reflection and
Josephson-like phenomena in the current-voltage characteristics of
inhomogeneous superconducting structures. I-V characteristics are
experimentally demonstrated in YBCO micro-constrictions with
potential applications in millimeter-wave and THz devices.

Identiferoai:union.ndltd.org:WATERLOO/oai:uwspace.uwaterloo.ca:10012/5252
Date25 May 2010
CreatorsGhohroodi Ghamsari, Behnood
Source SetsUniversity of Waterloo Electronic Theses Repository
LanguageEnglish
Detected LanguageEnglish
TypeThesis or Dissertation

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