Holographic properties of doubly doped lithium niobate crystals with Indium

The holographic properties of doubly doped lithium niobate crystals with Indium have been investigated. It is found that doping slight Indium concentration (0.5mol%) in LiNbO3:In, Fe crystal can efficiently increase the sensitivity with small dynamic range changing. To improve the whole holographic properties of LiNbO3 crystal, LiNbO3:In, Fe with ideal doping concentrations and a new photorefractive material LiNbO3:In, Mn have been proposed and achieved larger dynamic range, higher sensitivity and better signal-to-noise ratio than LiNbO3:Fe crystal (Fe:0.03wt.%) that is generally considered as a preferable storage medium in holographic memories. In a common volume of LiNbO3:In, Fe crystal proposed, 2030 holograms have been successfully multiplexed and exactly identified in a compact volume holographic data storage and correlation recognition system.