Nonlinear Self-Focusing of q-Gaussian Laser Beams in Plasma with Relativistic and Ponderomotive Effects under Linear Absorption
Abstract
The current study presents a theoretical analysis of nonlinear self-focusing of q-Gaussian laser beam transiting through unmagnetized plasma by incorporating simultaneous effects of relativistic mass variation and ponderomotive mechanism. Linear absorption is also included to account for energy dissipation during beam propagation. By applying WKB and paraxial approximations, the problem is reduced to 2nd order differential equation that governs the evolution of laser beam width as a function of normalized propagation distance. The resulting equation is solved numerically using 4th order Runge-kutta method. A systematic analysis is performed to examine effect of laser intensity, plasma density, absorption coefficient, q-parameter and initial beam radius on self-focusing dynamics of q-Gaussian laser beam. These findings indicate that laser-plasma parameters substantially affect beam dynamics and critically govern self-focusing process.
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