Abstract
A variety of novel dielectric THz waveguides were demonstrated to increase a channel capacity in a chip-to-chip communication system. Square holey cladding dielectric THz waveguides were designed, fabricated, and characterized. The single material holey cladding waveguide is low loss and easy to fabricate compared to doped core fibers. The square geometry supports two states of polarization with minimum cross-talk for polarization division multiplexing applications. Simulations show the waveguide supports two states of polarization across the frequency range of 180 GHz to 360 GHz. In addition, simulations show good mode isolation and low bending losses. Holey cladding square waveguide was fabricated using a custom-built draw tower to preserve the square geometry. TOPAS was chosen from several studied dielectrics for its low material loss and fabrication capabilities. Fabricated waveguides were shown to support the mode despite manufacturing defects. Fiber loss measurements showed a 24 dB/m loss that approach the accepted material loss of TOPAS (22 dB/m). THz vortex waveguides were demonstrated for space division multiplexing applications for the first time. The holey cladding TOPAS-based vortex waveguide was designed to preserve orbital angular momentum for l=1 and 2 at 280 GHz. The output power of the waveguide for different l and core sizes were studied. The waveguide was fabricated with the custom-built draw tower. Transmission of a first order OAM beam at 280 GHz was experimentally demonstrated. The first order, l=1, Laguerre-Gaussian beam was generated with a custom-made spiral phase plate. Inspired by the vortex waveguide design, several low-loss square holey core/cladding waveguides were designed and simulated for polarization division multiplexing. The waveguides combine the benefits of low loss and broadband transmission, while supporting two states of polarization. The boundary conditions created by the holey cladding confine the beam to the holey core for a low loss transmission. Three square holey core/cladding designs were proposed. These designs include a single-hole core, a nine-hole core, and a core comprised of four square capillary tubes. The square capillary tubes exhibits 7 dB/m, which is significantly lower than the material loss of TOPAS (22 dB/m).
Degree Date
Fall 12-16-2017
Document Type
Dissertation
Degree Name
Ph.D.
Department
Electrical and Computer Engineering
Advisor
Duncan MacFarlane
Number of Pages
150
Format
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Recommended Citation
Aflakian, Nafiseh, "Design, Fabrication, and Demonstration of Square Holey Dielectric THZ Waveguides" (2017). Electrical Engineering Theses and Dissertations. 4.
https://scholar.smu.edu/engineering_electrical_etds/4
