POLARIZED WAVE COUPLING AND SELECTION-RULES VIOLATION IN ALKALI-HALIDE CRYSTALS WITH F-A CENTERS

Self-diffraction of light has been investigated in KCl with F-A center s in order to elucidate the role of F-A-center kinetics in holographic recording under resonant optical excitation, It is shown that diffrac tion efficiency for holographic grating recorded in the spectral range of the F-A1 transition can be substantially increased by populating t he orientations which immediately interact with the polarized light by means of lateral illumination of the crystal with an auxiliary beam, The optimum range of auxiliary beam intensities leading to improvement bf grating quality is found, Such a range is directly defined by the parameter chi, characterizing the selection rules violation for F-A ce nter in KCl. It has been found that the experimentally determined valu e chi = 0.04 is consistent with the self-diffraction data obtained in this paper.