Growth and Photorefractive Effect of Ti and Fe Co-doped LiNbO3 Crystal
Ti:Fe:LiNbO3晶体的生长及其光折变性能的研究

Ti and Fe co-doped LiNbO3 crystals were grown from the melt by Czochralski method. The influence of different doping concentration on photorefractive effect was studied, the optical transmission spectra before and after reduction treatment were measured too. It was confirmed by ESR method that Ti ion exists in untreated Ti: Fe: LiNbO3 crystals in the form of Ti4+. It was supposed that the Fe2+ concentrations increase in untreated Ti: Fe: LiNbO3 crystal due to charge compensation effect. Without reduction treatment, the concentration of Fe2+ in crystals can be controlled by Ti dopping.The diffraction efficiency , which can be high up to over 90.00%, was also measured by using two-wave coupling technique. Ti: Fe: LiNbO3 crystal is a good new photorefractive material.