Inverse Faraday effect and Stokes drift in plasma

TL;DR

This paper refines the theoretical understanding of the inverse Faraday effect in plasma by accounting for the longitudinal beam component, revealing a higher demagnetization current that is balanced by an opposing magnetization current, thus preserving the effect.

Contribution

It introduces a more complete model of the IFE in plasma by including the longitudinal component, showing the demagnetization current is twice as large but balanced by an opposite magnetization current.

Findings

Peripheral demagnetization current is doubled when including the longitudinal component.

The increased demagnetization current is counteracted by an opposite magnetization current.

The inverse Faraday effect remains effective despite the revised current calculations.

Abstract

Recent theory of the light-induced medium magnetization (inverse Faraday effect, IFE) performed by a transversely-limited circularly-polarized light beam [Phys. Rev. B 91, 020411 (2015)] predicts the existence of a "demagnetization current" (DC) at the beam periphery which, apparently, acts oppositely to the light-induced rotational motion of the charge carriers inside the beam and thus reduces the IFE by the factor of 2. In this note, taking the longitudinal component of the beam into account, we show that the peripheral DC is two times higher than was calculated before. Nevertheless, this circumstance does not cancel the IFE because the DC, as a sort of Stokes-drift current in plasma [Phys. Rev. E 105, 065208 (2022)], is accompanied by the additional "magnetization current" of the opposite direction.