Thickness dependence of photo-induced light scattering in photorefractive ferroelectrics

Abstract

Stationary and dynamic properties of photo-induced light scattering (PILS) have been studied as a function of the photorefractive crystal thickness. A mono-exponential growth of the scattering amplification coefficient as well as a deceleration of the scattering recording dynamics is found with increasing crystal thickness. The experimental data set is analyzed by considering scattering centers located (i) in the crystal bulk or (ii) near to the crystal surface. By comparing experimental and theoretical results we can conclude that the major contribution to the output scattering signal originates from a thin crystal region frontier to the surface of light incidence (near-surface). The deceleration of the scattering dynamics is interpreted as the result of the competition between differently recorded noisy photorefractive gratings.