Numerical experiments on phase conjugation under conditions of stimulated Brillouin scattering of beams focused in a nonlinear medium

Three-dimensional calculations are reported of steady-state linear stimulated Brillouin scattering of linearly polarized beams representing a superposition of N_x X N_y Hermite–Gaussian modes with a random set of phases. It is shown that for N_x = N_y = 3–30 the wavefront reconstruction coefficient is relatively low, amounting to ~ 0.2–0.3. Calculations of the saturation conditions, carried out for two dimensions, showed that the reconstruction coefficient rises on increase in the efficiency of conversion of a pump beam to the energy of a Stokes wave. The calculated results are in agreement with the published experimental data.