Selective Erasure of Photorefractive Holograms in Fe∶LiNbO_3 by Introducing π Phase Shift on the Reference Wave

With the development of multiplexing holographic storage in Fe∶LiNbO 3, it′s absolutely necessary to modify or reedit the data stored in the crystal, so selective erasure is indispensable. In this paper, the principle of selective erasure and some methods for introducing π phase shift is reported, by recording the complementary hologram which leads to the complementary refractive index changes, the process of selective erasure can be realized. At the same time, some experiment results are also demonstrated and the analysis of these results are given.