The light-induced charge transport in LiNbO3:Mg, Fe crystals

Abstract
Light-induced charge transport properties of LiNbO3 crystals containing Mg dopants of different concentrations as well as Fe ions in different valence states are studied to obtain quantitative information on the influence of Mg. The experimental results indicate that the photovoltaic effect and the holographic sensitivity are mainly determined by the Fe2+ concentration and depend very weakly on Mg doping or the Li/Nb ratio in the crystals. The photoconductivity, however, increases considerably with increasing Mg concentration thus diminishing the saturation value of light-induced refractive index change.