Three-dimensional simulations of laser-plasma interactions at ultrahigh intensities

TL;DR

This paper uses 3D particle-in-cell simulations to explore how ultrahigh intensity lasers interact with dense matter, revealing relativistic penetration, self-focusing, and angular electron acceleration effects relevant to fusion and ion acceleration.

Contribution

It provides new insights into multi-dimensional laser-plasma interaction effects at ultrahigh intensities, including relativistic laser penetration and electron acceleration patterns.

Findings

Relativistic laser penetration up to critical density levels.

Strong self-focusing of laser pulses during interaction.

Annular electron heat flux indicating angular acceleration.

Abstract

Three-dimensional (3D) particle-in-cell (PIC) simulations are used to investigate the interaction of ultrahigh intensity lasers ($> 10^{20}$ W/cm$^{-2}$) with matter at overcritical densities. Intense laser pulses are shown to penetrate up to relativistic critical density levels and to be strongly self-focused during this process. The heat flux of the accelerated electrons is observed to have an annular structure when the laser is tightly focused, showing that a large fraction of fast electrons is accelerated at an angle. These results shed light into the multi-dimensional effects present in laser-plasma interactions of relevance to fast ignition of fusion targets and laser-driven ion acceleration in plasmas.