Raman-enhanced nonlinear effects on third harmonic generation in plasma using Hermite cosh Gaussian laser beam

This paper investigates the third harmonic generation (THG) process due to Stimulated Raman Scattering (SRS) in a magnetized plasma using a Hermite cosh Gaussian laser beam (HchG). The unique intensity profile of the HchG laser beam interacts with the plasma which leads to the generation of plasma waves and sideband electromagnetic waves i.e. stokes and Anti-stokes waves. This interaction leads to density perturbation inside the plasma, which couples with the laser wave, resulting in THG. A nonlinear wave equation, along with the equation of motion for plasma electrons, is employed to derive the dispersion relation and analyze the growth rate of the SRS instability. The study incorporates the effects of a static magnetic field, focusing on cold and underdense plasma conditions. The results demonstrate that the HchG beam’s spatial profile enhances the efficiency of THG and significantly impacts the growth rate and characteristics of SRS, suggesting that modulating laser beam profiles can effectively control plasma dynamics.