Two-beam coupling on the reflection grating in a Bi12TiO20 crystal

The results of experimental investigations of the dynamics of two-beam ampl ification on a reflection holographic grating and photoinduced absorption o f light at lambda = 633 rum in the (100) cut of a B12TiO20 crystal are pres ented. The numerical analysis of coupled-wave equations taking into account the absorption of light and the vector nature of the coupling in a gyrotro pic cubic crystal with a given orientation is carried out. The processing o f the experimental data using the scalar approach shows that the two-beam g ain on a diffusion-type reflection grating in the B12TiO20 crystal may achi eve 4.7 cm(-1) while the additional absorption induced by light amounts to 0.65 cm(-1).