Investigation of Laser Plasma Instabilities driven by Coupled High-Power Laser Beams in Magnetized Underdense Plasmas

Abstract

Stimulated Brillouin and Raman scattering (SBS and SRS) are instabilities that affect the propagation of high-power lasers in plasmas. The latter is further affected by Cross-Talk (CT) effects when multiple laser beams are simultaneously propagated in the plasma, as found in the schemes proposed for inertial confinement fusion (ICF). Here we develop a new theoretical model that allows us to evaluate the impact of CT on SBS and SRS in low-density plasmas. As supported by experiments, we demonstrate that CT can lead to a reduction of both SBS and SRS, due to the destabilization of the individually triggered instabilities. We further demonstrate that this destabilization effect is accelerated by applying an externally magnetic field to the plasma, which is also beneficial for the hydrodynamics or fuel heating of ICF. By shedding new light on the promising scheme of magnetized ICF, our findings thus offer beneficial prospects for ICF.