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Optimization of fixed diffraction efficiency for LiNbO3:Cr:Cu crystal by optimal switching time

An oscillatory characteristic of diffraction is observed during holographic recording period in an oxidized LiNbO3:Cr:Cu crystal with 514 nm green light as the recording light and 390 nm UV light as the sensitizing light. The optimal switching time from the recording step to the fixing step for high diffraction of a fixed hologram is studied. It is shown that switching after the first diffraction maximum leads to higher fixed diffraction efficiency. The theoretical explanation is presented according to time-space dynamic theory of the nonvolatile holographic recording in doubly-doped LiNbO3 crystals.