Kinetics of Photorefractive Light Scattering in LiNbO_3:Cu and LiNbO_3:Zn Single Crystals

摘要

Results of studies of the kinetics of photorefractive light scattering (PRLS) in optically nonlinear congruent single crystals of lithium niobate {LiNbO_3, Li/Nb = 0.946) containing multivalent cation admixtures of Cu [0.015 mass %] ( "photorefractive ") and Zn [0.5 mass %] ( "non-photorefractive ") are reported. The shape of the PRLS indicatrix is found to be different in case of Cu and Zn admixtures. However, the angular widening of the indicatrix in both cases reaches its stationary value faster at higher laser radiation intensities. The PRLS is found to depend on the site of the ingot from which the samples are cut - an evidence of non-uniform distribution of defects with localised electrons determining the photorefractive effect in the bulk of the single crystal ingot.