MECHANISM OF SELF-PUMPED PHASE-CONJUGATION BY NEAR-FORWARD STIMULATEDSCATTERING OF HETEROGENEOUS LASER-BEAMS IN NEMATIC LIQUID-CRYSTAL

The conditions of self-pumped phase conjugation of an Nd:YAG laser bea m with a heterogeneous space structure by stimulated thermal scatterin g in a nematic liquid crystal layer with a mirror are investigated exp erimentally and theoretically. It is shown that phase conjugation by n ear-forward simultaneous scattering of two laser beams (incident and m irror-reflected) is realized when the diffraction length of the pumpin g beam is comparable with the nonlinear layer thickness and the incide nce angle is less than the diffraction divergence angle.