Growth and photorefractive properties of Mg:Ce:Fe:LiNbO3 crystals

The congruent Ce(0.1 mol%):Fe(0.03 wt%):LiNbO3 crystals doped with different concentrations of 2.0 mol%, 4.0 mol% and 6.0 mol% MgO were grown by the Czochralski method. Content of impurities was analyzed by means of Ultraviolet (UV)-Visible (Vis) spectroscopy. The photorefractive properties of the Mg:Ce:Fe:LiNbO3 crystals were experimentally studied by using the two-wave coupling method. The results of the two-wave coupling experiments showed that as the doping concentration of Mg increased, the diffraction efficiency decreased, but the holographic response time and photorefractive sensitivity increased. The photorefractive sensitivity and dynamic range improve obviously when used the 532 nm laser as light source instead of 633 nm laser.