NONLINEAR OPTICAL MATERIAL AND ITS PRODUCTION

PROBLEM TO BE SOLVED: To increase the performance coefft., specially the performance coefft. in a nonresonance region by individually dispersing metallic fine particles in a light-transmitting substrate and preparing the substrate as a single crystal. SOLUTION: This nonlinear optical material consists of a light-transmitting substrate and fine particles of at least one kind of metal individually dispersed in the substrate. The substrate is made of a single crystal. Since the metallic fine particles are confined three-dimensionally in the light-transmitting substrate, nonlinearity is obtd. by, for example, excitation of the surface plasmon of the metallic fine particles and the quantum size effect. As a result, a nonlinear optical material having optical bistability and an optical relaxation time in pico seconds order is realized and it can be used for an optical switch or an optical wavelength convertor such as THG. Thereby, the obtd. nonlinear optical material has large performance coefft. x /α (α is the absorption coefft.) and especially, large x /α in a nonresonance region.