Abstract
We study the temperature and pump-intensity dependence of the temporal evolution of photoinduced light scattering in congruent, hafnium-codoped and near-stoichiometric LiNbO3:Fe crystals. A partial self-recovery process is found in the evolution trend of photoinduced light scattering in all crystals at room temperature while it disappears at -190 degrees C or above 120 degrees C. Moreover, a "scattering acceleration effect" is found for both Hf-doped and near-stoichiometric crystals. Basing the saturation refractive-index modulation the partial self-recovery process is explained by the slow recombination of light-induced space charges of the noise gratings with high wave vectors. The "scattering acceleration effect" is connected with the activation of the protons located around Fe ions and their impact on the photoconductivity. (C) 2016 Optical Society of America