Generation of the longitudinal current by the transversal electromagnetic field in classical and quantum plasmas

TL;DR

This paper derives formulas for electric currents in classical and quantum collisionless plasmas, revealing that nonlinear effects induce a longitudinal current orthogonal to the known transverse current, with results applicable at any temperature and wave number.

Contribution

It introduces a unified approach to calculate electric currents in classical and quantum plasmas, highlighting the emergence of a longitudinal current due to nonlinear effects.

Findings

Longitudinal current appears due to nonlinearity in plasma response.

Size of longitudinal current is similar in classical and quantum plasmas at small wave numbers.

Graphical comparison shows quantum and classical currents are comparable.

Abstract

From Vlasov kinetic equation for collisionless plasmas distribution function in square-law approximation on size of electromagnetic field is received. Formulas for calculation electric current at any temperature (any degree of degeneration of electronic gas) are deduced. The case of small values of the wave numbers is considered. It is shown, that the nonlinearity account leads to occurrence the longitudinal electric current directed along a wave vector. This longitudinal current orthogonal to known transversal classical current, received at the linear analysis. From the kinetic equation with Wigner integral for collisionless quantum plasma distribution function is received in square-law on vector potential approximation. Formulas for calculation electric current at any temperature are deduced. The case of small values of wave number is considered. It is shown, that size of a longitudinal current at small values of wave number and for classical plasma and for quantum plasma coincide. Graphic comparison of dimensionless size of a current quantum and classical plasma is made.