Self-Focusing of Gaussian Laser Beam in Unmagnetized Plasma Described by Kappa Distribution

Empirical kappa distributions have become increasingly widespread across space and plasma physics. In the present paper, logical straightforward extension of dielectric function of plasma described by Kappa parameter is employed to study the interaction of Gaussian laser beam with plasma. The nonlinear differential equation describing evolution of beam-width parameter is established by using parabolic wave equation approach under WKB and paraxial approximations. The effects of Kappa parameter and ratio of the thermal velocity of plasma electrons to the velocity of light on the propagation dynamics of Gaussian laser beam in non-Maxwellian plasma are specifically inspected. It is shown that the larger Kappa parameter and thermal velocity of electrons become more significant for stronger self-focusing of Gaussian beam in plasma. This enables the need of more exploration of physical mechanisms involved in the field of interaction of lasers with non-Maxwellian plasma.