UNIFORMITY OF HOLOGRAM RECORDING AND WEAK-BEAM AMPLIFICATION IN LINBO3 FOR ILLUMINATION BY BEAMS WITH ORTHOGONAL AND PARALLEL POLARIZATION

Some results of photorefractive investigations in LiNbO3 are not expla ined within well-accepted models [1]. New qualitative explanations are proposed, showing that the hologram recording by beams both with orth ogonal and with parallel polarizations is caused by the photovoltaic c urrent flowing along a polar axis. In this paper the model is proposed which explains physical foundation of nonshift hologram amplification . We have demonstrated that the big nonstationary amplification is cau sed by a recording in transition period.