Simulations of Magnetic Field Generation in Unmagnetized Plasmas via Beat Wave Current Drive

TL;DR

This paper presents simulation results demonstrating how beat wave current drive can magnetize unmagnetized plasmas, showing electron acceleration, current generation, and magnetic field creation with high efficiency, potentially enabling new plasma experiments.

Contribution

The study provides the first detailed 2D simulation analysis of beat wave current drive for plasma magnetization, revealing new effects and efficiency metrics.

Findings

Beat wave generation matches theoretical predictions.

Electron acceleration leads to current and magnetic field generation.

Wave to magnetic energy conversion efficiency reaches 0.2%.

Abstract

This work describes the scientific basis and associated simulation results for the magnetization of an unmagnetized plasma via beat wave current drive. Two-dimensional electromagnetic particle-in-cell simulations have been performed for a variety of angles between the injected waves to demonstrate beat wave generation in agreement with theoretical predictions of the beat-wave wave vector and saturation time, revealing new 2D effects. The simulations clearly demonstrate electron acceleration by the beat waves and resultant current drive and magnetic field generation. The basic process depends entirely on the angle between the parent waves and the ratio of the beat-wave phase velocity to the electron thermal velocity. The wave to magnetic energy conversion efficiency of the cases examined is as high as 0.2%. The technique could enable novel plasma experiments in which the use of magnetic coils is infeasible.