Optical bleaching effect in a BiI₃ microcluster colloid by saturated absorption spectroscopy

Abstract

An optical bleaching effect in a BiI₃ microcluster colloidal system in the visible region was observed. We find that this effect can be adequately explained by a two-level model with inhomogeneous broadening. By measuring the intensity dependence of the saturated absorption coefficient, we evaluated the third- and fifth-order effective nonlinear-optical susceptibilities of the BiI₃ microcluster colloidal system to be approximately 10⁻¹⁰ and 10⁻¹⁵ esu, respectively. By applying the effective-medium approximation, we find that the third-order nonlinear-optical susceptibility of BiI₃ microclusters is approximately 5 × 10⁻⁶ esu.

© 1992 Optical Society of America