Title page for etd-0629114-150220


[Back to Results | New Search]

URN etd-0629114-150220
Author Hung-hsuan Chen
Author's Email Address No Public.
Statistics This thesis had been viewed 5354 times. Download 45 times.
Department Electro-Optical Engineering
Year 2013
Semester 2
Degree Master
Type of Document
Language zh-TW.Big5 Chinese
Title Mach-Zehnder Interferometers and Micro-Racetrack Resonators Based on Subwavelength Grating Waveguides
Date of Defense 2014-07-16
Page Count 83
Keyword
  • Refractive index sensitivity
  • Mach-Zehnder Interferometer
  • Subwavelength grating
  • Temperature sensitivity
  • Micro-Racetrack Resonator
  • Delocalized mode
  • Abstract Recently, subwavelength grating (SWG) waveguides have been proposed to guide light in silicon on insulator (SOI) structures with more extended field in the cladding regions. SWG waveguides are formed by periodically interlacing silicon segments at the subwavelength scale buried in a material with smaller refractive index. By varying the size of silicon segments or the index of the surrounding material, we can easily modulate the optical characteristics of the SWG waveguides.
    In this thesis, we numerically investigate the optical characteristics of straight and bent SWG waveguides by utilizing a 2-D finite element method (FEM). In order to suppress the high bending losses resulted from the delocalization of mode field in SWG waveguides, we propose a improved bent SWG waveguide to reduce the bending loss. We have also employed SWG waveguides into SOI-based Mach-Zehnder interferometers. Due to the effective modal index difference between the SWG waveguide and the conventional SOI waveguide, we can successfully obtain the interference spectrum from the Mach-Zehnder interferometer. The simulation results show that the refractive index sensitivity of the proposed Mach-Zehnder interferometer is raised by the delocalized mode of the SWG waveguide and increased with a0 for a fixed Λ. The highest sensitivity is 1850nm/RIU as a0=0.2μm. Besides, we also apply SWG waveguides into the SOI-based micro-racetrack resonators. The coupling efficiency between the bus and the ring resonator can be improved by the delocalized mode. The results show that the refractive index sensitivity is 62nm/RIU, and the SWG micro-racetrack resonators possess a smaller temperature sensitivity of 75pm/oC due to the composite structure of the SWG waveguide.
    Advisory Committee
  • Wood-Hi Cheng - chair
  • Hung-wen Chang - co-chair
  • Jui-Yang Feng - co-chair
  • Chin-Ping Yu - advisor
  • Files
  • etd-0629114-150220.pdf
  • Indicate in-campus at 5 year and off-campus access at 5 year.
    Date of Submission 2014-07-29

    [Back to Results | New Search]


    Browse | Search All Available ETDs

    If you have more questions or technical problems, please contact eThesys