Optical Properties of Lithium Niobate Waveguides, and Prism Coupling for Optimizing Waveguide Fabrication.
Abstract
I investigated the accuracy and precision of effective index of refraction measurements using prism coupling. I found that the coupling gap's geometry is critical to predicting the accuracy and resolution of measurements. I provide experimental evidence that there are advantages to using high coupling pressures that yield long coupling lengths. I present and evaluate an experimental technique aimed at reducing the effects of perturbation and find that it may not be applicable to all situations. I extend a previous model of prism coupling to include a finite coupling length. Also, I introduce an alternative model of prism coupling based upon a local normal-mode expansion and present its preliminary numerical results. I have observed more extraordinary polarized guide modes near cut-off in Ti in-diffused lithium niobate planar waveguides than are predicted by Ti in-diffusion models. I also observe these nearly cut-off modes in lithium niobate specimens fabricated without Ti under a variety of diffusion atmospheres. Values of the effective index of these nearly cut-off modes found do not agree with those calculated. jg
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 25, 1995
- Accession Number
- ADA294111
Entities
Organizations
- University of Colorado Boulder