STRESS-ANALYSIS METHOD FOR OPTICAL WAVEGUIDES COMPOSED OF ELASTICALLY ANISOTROPIC MATERIALS AND ITS APPLICATION TO STRAIN-INDUCED OPTICAL WAVEGUIDES

In this paper we propose a new stress analysis method that can evaluate the residual thermal stress distribution in an optical waveguide with an elastically arbitrary anisotropy. We analyze the optical waveguide by taking into account the refractive index change obtained from stress analysis. A rigorous evaluation of the propagation characteristics in a strain-induced optical waveguide is now possible. Since the finite-element method is used for both the stress analysis and the optical waveguide analysis, the complex refractive index change obtained from stress analysis can be faithfully reflected in the optical waveguide analysis. Strain-induced optical waveguides with a SiO2/GaAs structure and a SiO2/LiNbO3 structure are chosen. The stress and strain in the waveguide and the change of the refractive index profile are obtained numerically and their effects on the transmission characteristics of the optical wave are studied. To the best of our knowledge, this is the first time that an optical waveguide analysis has been carried out from stress analysis taking into account an anisotropy. © 1998 Scripta Technica, Electron Comm Jpn Pt 2, 81(5): 16–23, 1998