Influences of iron doping on the photorefractive properties of KTa1−<i>x</i>Nb<i>x</i>O3 crystals

Abstract

The influences of iron doping on the photorefractive properties of KTa1−xNaxO3 (KTN) crystals were studied. The two-wave-mixing gain coefficients and the grating formation rates were measured in undoped and Fe-doped KTN samples. Photorefractive parameters, such as the effective carrier number density, were determined for these samples. It was shown that the gain coefficient increases significantly with the doped Fe content, but the grating formation rate decreases with it, and that all the influences of iron doping originate mainly from the variation of the effective carrier number density.