Reduced KNbO3 crystals for fast photorefractive nonlinear optics

Abstract

Reduced KNbO3 crystals are shown to have the fastest photorefractive response times for applications in the visible wavelength region. Grating build-up times at cw illumination in the microsecond region are reported which allow the use of such crystals for real-time applications. The reduction treatment and a new method for the investigation of the photorefractive homogeneity during reduction are presented.