Study of coexisting stimulated Raman and Brillouin scattering at relativistic laser power

This paper presents a model to study the stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS) simultaneously at relativistic laser power. At high intensity, the relativistic mass correction for the plasma electrons becomes significant and the plasma refractive index gets modified which leads to the relativistic self-focusing of the pump beam. This filamentation process affects the scattering processes (SRS and SBS) and at the same time the pump filamentation process also gets modified in the presence of the coexisting SRS and SBS due to the pump depletion. We have also demonstrated that the pump depletion and relativistic filamentation affects the back-reflectivity of scattered beams (SRS and SBS) significantly, for the coexistence case.