This work is concerned with the modeling and analysis of lossy planar dielectric
optical waveguides. Loss mechanisms which affect propagation characteristics are
reviewed, and various representations of the propagation constant in the lossy case
are defined. Waveguide structures which are susceptable to absorption and/or to
leakage loss, in particular silicon-based structures, are discussed. The modeling and
analysis of these waveguides by various computational techniques is considered.
Two computational methods, the commonly used transfer matrix method and
the recently developed impedance boundary method of moments (IBMOM), are reviewed
and extended to the complex domain. A third computational method, which
offers improved convergence of the IBMOM for structures with large stepwise changes
in refractive index, is formulated. In this approach, the regions containing refractive
index discontinuities are replaced by equivalent extended impedance boundary conditions,
and expansion of the transverse field in the remaining region of continuous
refractive index profile is carried out. A significant increase in the rate of convergence
is demonstrated for various waveguide structures, including an anti-resonant
reflecting optical waveguide (ARROW) structure.
Two applications of the IBMOM with extended impedance boundary conditions
are presented. In the first, the method is applied to the design of a chemical sensor.
The sensor, a silicon-based ARROW structure, is designed to measure the refractive
index of certain chemical substances with a high degree of accuracy. In a second
application, graded index SiON waveguides fabricated at Oregon State University are
characterized and compared to the theoretical model. Excellent agreement between the theoretical and measured coupling angles is shown. / Graduation date: 1996
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/34928 |
| Date | 20 June 1995 |
| Creators | Remley, Catherine A. |
| Contributors | Weisshaar, Andreas |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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