Features of Propagation of Electromagnetic Waves in Sol-Gel Optical Waveguides under Varying Temperature

Abstract

Features of the temperature dependence of effective refractive index n_eff (ERI) of optical waveguides based on sol-gel materials have been studied and behavior of the ERI temperature coefficient (TC) have been determined. It has been found experimentally and theoretically that, with properly selected film parameters, the ERI TC can have a negative, zero, or even small positive value within a certain temperature range. Clear mathematical description of the dependence of the ERI TC on the waveguide parameters and the partial power of the wave in the waveguide has been given.