Stimulated Brillouin scattering in the strong coupling regime

Abstract

Stimulated Brillouin scattering (SBS) has been reexamined in the strong coupling limit. The three‐wave interaction in the strong coupling regime, which gives rise to a purely growing mode for wave numbers k≳2k₀, where k₀ is the wave vector of the pump wave, has been studied. This regime was first found by Cohen and Max [Phys. Fluids 22, 1121 (1979)]. In this regime, for a flowing plasma, a significant portion of the unstable spectrum is found to be blueshifted even for the Mach number equal to unity. For the inhomogeneous case, the convective gain in the strong coupling limit turns out to be identical to the gain in the SBS in the weak coupling limit regime.