Modeling the electron density distribution with a nonthermal-nonextensive function for nonlinear laser–plasma interactions
摘要
The mixed nonthermal-nonextensive electron density distribution function is increasingly used to describe various types of plasmas, but to the best of our knowledge, there is no report on the use of this new kind of functions to describe nonlinear laser-collisionless plasma interaction with the approach proposed here. In this contribution, we generalized the Tribeche-Tsallis-Cairns hybrid distribution to describe our plasma by the above-mentioned function, and nonextensive ions. By using the Maxwell equations, the relativistic two-fluid model and the slowly-varying-amplitude approximation, we derived equations for the description of the nonlinear dynamics of a circularly-polarized laser-beam interacting with collisionless non-Maxwellian magnetized plasma. Taking into account the ponderomotive force, the external magnetic field, and other plasma parameters, we found that the latter cause and affect some nonlinear phenomena in the considered plasma. These phenomena include the modulational instability (MI), the envelope solitary waves, and the laser-beam self-focusing. The present work investigates analytically and numerically these nonlinear phenomena. The results show that the existence of the electron density, with a high-energy particles hybrid distribution function tail, and other factors play an essential role in the plasma nonlinearity features. We noted that the more the electron and ion density distributions tend to the Maxwellian form, the nonlinearity and the MI’s growth rate increase, the envelope solitary waves amplitude decreases, and the laser-beam self-focusing property enhances. Our contribution generalizes some previous models describing laser-plasma interactions, and suggests that the above-mentioned function could be a good candidate to describe simulations and experiments involving nonlinear laser-collisionless plasma interactions.