Nonlinear-optical properties of semiconductor composite materials

Abstract

The propagation of electromagnetic waves in a nonlinear medium composed of semiconductor microcrystallites embedded in a host medium has been investigated. Explicit results are given for the case of cadmium sulfide grains in glass when a saturable two-level approximation is used for the nonlinear dielectric function. The bistable behavior, noticed earlier by Chemla and Miller [ Opt. Lett.11, 522 ( 1986)], for single grains is manifested in the propagation studies conducted here by the occurrence of a discontinuity in the index of refraction in the medium. Various approximations are used to obtain the optical bistability properties. Possible applications of this feature are pointed out.