Effect of light intensity on quasi-nonvolatile holography in doubly doped LiNbO_3:Fe:Ru crystal

摘要

One-color photorefractive holography has been investigated in the oxidized LiNbO_3:Fe:Ru crystal with recording wavelength 632.8nm. The crystal shows a high asymmetric behavior in grating buildup and readout erasure rates. This remarkable property shows that the recorded grating is quasi-nonvolatile during readout. In this paper, the effect of the pre-sensitizing process and the readout intensity on the asymmetric behavior is investigated experimentally, the results show that the recording sensitivity can be increased by the pre-sensitizing process, and the grating lifetime can be extended by increasing readout light. At last, the reason for the high asymmetry is explained qualitatively in terms of a multiple center model.