Influence of oxidizing treatments on the photorefractive properties of ferroelectric lead germanate crystals

Abstract

The influence of oxidizing treatments on the photorefractive properties of nominally pure ferroelectric lead germanate crystals is investigated. In two-wave mixing experiments the dark conductivity, the intensity dependence of the photoconductivity, the effective charge density and the factors that reduce the space-charge field are determined. Oxidizing treatments increase the photoconductivity and the effective charge density, but decrease the electron-hole-competition factor. The experimental results can be explained in terms of a one-center model with electron-hole competition.