Fast photorefractive response in LiNbO3 crystal co-doped with Fe/Sm ions

Sm:Fe:LiNbO3 crystal was grown by doping Sm2O3 in Fe:LiNbO3 crystal. The exponential gain coefficient, diffraction efficiency and photorefractive response time were measured by two-wave mixing experiment, respectively. It was found that the response speed was greatly improved by doping Sm ions in Fe:LiNbO3 crystal. Our analysis also showed that photoconductivity enhancement was responsible for improving the response speed in the Sm:Fe:LiNbO3 crystal.