IMPROVED DEVELOPMENT OF THERMALLY FIXED HOLOGRAMS IN PHOTOREFRACTIVE LINBO3 CRYSTALS WITH HIGH-INTENSITY LASER-PULSES

Holographic gratings were thermally fixed in iron-doped photorefractiv e LiNbO3 crystals and developed with frequency-doubled Q-switched puls es of a Nd:YAG laser (light wavelength, 532 nm; pulse duration, 3 ns). The saturation values of the diffraction efficiency increased with in creasing pulse light intensity. Compared with development with cw ligh t, high-intensity laser pulse development resulted in an enlargement o f the diffraction efficiency of a factor of similar to 2. A contributi on of the intrinsic defect Nb on Li site to the charge transport is mo st probably the origin of this effect. The results are useful, e.g., f or improvements of volume holographic memories and wavelength filters. (C) 1998 Optical Society of America.