Holographic storage performance of iron-doped LiNbO3

Iron doped LiNbO3has been found to give very sensitive performance in holographic storage applications, permitting exposures nearly 1000 times shorter than the undoped crystals. Crystals doped during growth exhibit an interesting combination of increased sensitivity and higher optical erasure resistance, indicating that there is a marked difference between the recording and erasure efficiencies. While the increased erasure resistance is a desirable property in applications requiring repeated non-destructive readout, it is an undesirable feature in dynamic applications requiring fast read-write cycles. Efforts to develop materials that do not exhibit high erasure resistance included double-doping the samples with Fe and various possible charge-compensating centers, and iron-doping by diffusion as opposed to doping the crystals during growth.