Investigation on nonvolatile holographic storage properties in Hf:Ru:Fe:LiNbO3 crystals as a function of Li composition

A series of Hf: Ru: Fe: LiNbO3 crystals with various Li composition in the melt were grown by the conventional Czochralski method via the optimum growth condition in the air. The intrinsic defect concentrations and structures of lithium niobate crystals were investigated by using XRD technique and the holographic storage properties were investigated by means of two-wavelength nonvolatile experiments. The results indicate that the concentration of intrinsic defects decreases with the increasing of Li/Nb ratio and the holographic storage properties is obviously improved. The Hf: Ru: Fe: LiNbO3 crystal with Li/Nb ratio 1.38 has the best holographic storage properties. The experiment results indicated that Hf: Ru: Fe: LiNbO3 crystal was an outstanding medium for holographic storage applications.