Abstract

Liquid Crystals (LCs) are by far extensively studied in integrateci optics because of their exceptional mechanical and optical properties, and a lot of optical devices for guided optics, based on linear and nonlinear effects in these materials, have been proposed.¹ Efficient control of the guided light can be obtained, for example, acting on the LC placed in the substrate^2,4 or in the core³ of a slab waveguide with an external (electric, mag netic, or optical) field. In this work, instead, we study the self action of an intense optical field propagating in the waveguide core made of a liquid crystal material. Strong planar alignment of the LC molecules is assumed at the walls and only TM modes are considered. (It can be shown that, above a critical threshold of the guided power, such a nonlinear structure cannot support pure TE modes.) Moreover, the waveguide is assumed to be symmetric, so that only even or odd modes are supported.

© 1994 IEEE