Temperature Effect on Self-Focusing and Defocusing of Gaussian Laser Beam Propagation Through Plasma in Weakly Relativistic Regime

The propagation characters of an intense Gaussian laser beam in underdense plasma are investigated taking into account the combined effects of relativistic and ponderomotive nonlinearities. The nonlinear second-order differential equation of the dimensionless beamwidth parameter is obtained and numerically solved. The effect of initial electron temperature on self-focusing and defocusing of Gaussian laser beam propagation in plasma are studied. Moreover, the behavior and variation of modified electron density and laser beam intensity as a function of plasma length in both self-focusing and defocusing regimes are discussed.