Conversion efficiency and energy balance in stimulated backscattering

An experimental investigation was made of the conversion efficiency and energy balance in stimulated Brillouin scattering (STBS) in various liquids and numerical solutions were obtained of a system of nonlinear equations describing approximately the conversion of pump radiation into STBS light in the presence of two-photon absorption. The experimental results and those obtained by an approximate theoretical calculation indicated that the influence of two-photon absorption was strongest near the STBS threshold. When the efficiency of conversion of pump radiation into STBS light was high, the influence of two-photon absorption decreased because of effective weakening of the field in a cell.