Radiation reaction force induced nonlinear mixing of Raman sidebands of an ultra-intense laser pulse in a plasma

TL;DR

This paper investigates how radiation reaction forces influence the nonlinear mixing of Raman sidebands in ultra-intense laser-plasma interactions, revealing enhanced Raman scattering instability due to radiation effects.

Contribution

It introduces a perturbative approach to include radiation reaction in plasma electron dynamics, showing its effect on Raman sideband mixing and instability growth.

Findings

Radiation reaction causes phase shifts in nonlinear current densities.

Enhanced growth of forward Raman scattering instability observed.

Nonlinear mixing of Raman sidebands is significantly affected by radiation forces.

Abstract

Stimulated Raman scattering of an ultra-intense laser pulse in plasmas is studied by perturbatively including the leading order term of the Landau-Lifshitz radiation reaction force in the equation of motion for plasma electrons. In this approximation, radiation reaction force causes phase shift in nonlinear current densities that drive the two Raman sidebands (anti-Stokes and Stokes waves), manifesting itself into the nonlinear mixing of two sidebands. This mixing results in a strong enhancement in the growth of the forward Raman scattering instability.