Relativistic cross-focusing of Gaussian laser beams in thermal quantum plasma

Abstract

Recent work focuses on propagating two intense Gaussian laser beams in thermal quantum plasma considering the relativistic regime. The presence of a second beam affects the focus of another beam in plasma and cross-focusing occurs. Considering the dependence of plasma nonlinearity on the intensity of both beams, an expression for the nonlinear dielectric constant of plasma has been estimated. Nonlinear partial differential coupled equations governing the dynamics of two beams in the thermal plasma are obtained by assuming a quantum hydrodynamic model. The obtained equations are solved numerically using the paraxial ray approximation and the fourth-order Runge-Kutta method. The numerical results show that the second beam strengthens the relativistic factor. Furthermore, variations of the beam width parameter and the laser intensity are investigated with and without the cross-focusing mechanism. This study presents that the cross-focusing enhances laser focusing. The results could be useful in understanding the mechanism of the laser propagation in the quantum plasma that is important in the fast ignition of modern ICF experiments, where deuterium-tritium plasma is compressed by intense laser beams and the quantum effects are dominant.