# Amplification of mid-infrared lasers via magnetized-plasma coupling

## TL;DR

This paper systematically analyzes how external magnetic fields influence the coupling in plasma-based mid-infrared laser amplification, revealing dependencies on various plasma and wave parameters to optimize performance.

## Contribution

It provides a detailed numerical evaluation of the magnetized three-wave coupling coefficient for mid-infrared laser amplification in plasma, considering multiple physical parameters.

## Key findings

- Coupling varies significantly with wave propagation angle and polarization.
- Magnetic fields alter the coupling compared to unmagnetized Raman and Brillouin processes.
- The study maps out parameter dependencies for optimized laser amplification.

## Abstract

Plasmas may be used as gain media for amplifying intense lasers, and external magnetic fields may be applied to improve the performance. For mid-infrared lasers, the requisite magnetic field is on megagauss scale, which can already be provided by current technologies. Designing the laser amplifier requires knowing the magnetized three-wave coupling coefficient, which is mapped out systematically in this paper. By numerically evaluating its formula, we demonstrate how the coupling depends on angle of wave propagation, laser polarization, magnetic field strength, plasma temperature, and plasma density in the backscattering geometry. Since the mediation is now provided by magnetized plasma waves, the coupling can differ significantly from unmagnetized Raman and Brillouin scatterings.