Effect of Plasma Mode Frequency on Gaussian Laser Beam in Hot Plasma

Abstract

The effect of plasma mode frequency on Gaussian laser beam in hot plasma was investigated, and the impact of ponderomotive force and electron temperature was taken into consideration The conductivity tensor of hot plasma was defined and the wavenumber as a function of plasma mode frequency was determined. Analytical methods were used to derive Gaussian parameters with respect to the frequency of the plasma mode. The current density induced by ponderomotive force significantly changes the dielectric constant of hot plasma. We found that waist, spot size, radius of curvature, and Gouy phase of Gaussian laser beam exhibit rapid decrease as plasma mode frequency increases, while the beam intensity follows a bell-shaped profile, which increases rapidly at the waist and decreases toward the edges. The results show that the laser beam becomes narrower and its intensity becomes higher than in vacuum. This phenomenon has complex nonlinear implications; it impacts self-focusing, self-modulation, generation of harmonics, and sidebands. Tightly focused beam conserves energy and improves energy transfer, providing efficiency in material handling and spectroscopy. The results presented in this work can be useful for advancing our plasma.