Twisted plasma waves driven by twisted ponderomotive force

TL;DR

This paper demonstrates the generation of twisted plasma waves driven by twisted ponderomotive force using Laguerre-Gaussian laser pulses, revealing nonlinear effects and angular momentum transfer through 3D particle-in-cell simulations.

Contribution

It introduces a novel method to generate twisted plasma waves via co-propagating LG laser pulses with different frequencies and twist indices, supported by detailed simulations and theory.

Findings

Twisted plasma waves exhibit helical electron density perturbations.

Nonlinear rotating currents and static axial magnetic fields are observed.

Particles carry axial orbital angular momentum in the plasma waves.

Abstract

We present results of twisted plasma waves driven by twisted ponderomotive force. With beating of two, co-propagating, Laguerre-Gaussian (LG) orbital angular momentum (OAM) laser pulses with different frequencies and also different twist indices, we can get twisted ponderomotive force. Three-dimensional particle-in-cell simulations are used to demonstrate the twisted plasma waves driven by lasers. The twisted plasma waves have an electron density perturbation with a helical rotating structure. Different from the predictions of the linear fluid theory, the simulation results show a nonlinear rotating current and a static axial magnetic field. Along with the rotating current is the axial OAM carried by particles in the twisted plasma waves. Detailed theoretical analysis of twisted plasma waves is given too.