Suppression of power losses during laser pulse propagation in underdense plasma slab

TL;DR

This paper investigates how multi-colored lasers with specific frequency detuning can suppress dominant scattering mechanisms in underdense plasma, enabling more efficient laser power transmission during plasma interactions.

Contribution

It introduces a method using multi-colored lasers with frequency detuning to suppress FRS, improving power transmission in plasma.

Findings

Multi-colored lasers suppress FRS in underdense plasma.

Power losses are reduced during laser propagation.

Efficient laser transmission achieved with frequency detuning.

Abstract

For current state-of-the-art terawatt lasers, the primary laser scattering mechanisms in plasma include Forward Raman Scattering (FRS), excitation of plasma waves, and the self-modulational instability (SMI). Using 2D PIC simulations, we demonstrate the dominance of the FRS in the regime with medium-to-low density plasma and non-relativistic laser fields. However, the use of multi-colored lasers with frequency detuning exceeding the plasma frequency, $\Delta \omega >\omega_{\rm pe}$, suppresses the FRS. The laser power can then be transmitted efficiently.