# The occurrence of transverse and longitudinal electric currents in the classical plasma under the action of N transverse electromagnetic waves

## TL;DR

This paper investigates how multiple electromagnetic waves induce both transverse and longitudinal electric currents in classical plasma, revealing nonlinear effects that generate a longitudinal current orthogonal to the linear transverse current.

## Contribution

It derives a distribution function and current formula showing nonlinear plasma response to multiple electromagnetic waves, highlighting the emergence of a longitudinal current.

## Key findings

- Longitudinal current appears due to nonlinearity in plasma response.
- Longitudinal current is orthogonal to the linear transverse current.
- Results are valid for small wave numbers.

## Abstract

Classical plasma with arbitrary degree of degeneration of electronic gas is considered. In plasma N (N>2) collinear electromagnatic waves are propagated. It is required to find the response of plasma to these waves. Distribution function in square-law approximation on quantities of two small parameters from Vlasov equation is received. The formula for electric current calculation is deduced. It is demonstrated that the nonlinearity account leads to occurrence of the longitudinal electric current directed along a wave vector. This longitudinal current is orthogonal to the known transversal current received at the linear analysis. The case of small values of wave number is considered.