Observation of post-soliton expansion following laser propagation through an underdense plasma

TL;DR

This study observes and characterizes the expansion of post-solitons in underdense plasma after laser interaction, providing insights into their dynamics and polarization dependence through experiments and simulations.

Contribution

It presents the first detailed experimental observation and analysis of post-soliton expansion in underdense plasma, including comparison with models and 3D simulations.

Findings

Post-solitons persist up to 100 ps after laser pulse.

Expansion dynamics depend on polarization.

Experimental results agree with analytical and simulation models.

Abstract

The expansion of electromagnetic post-solitons emerging from the interaction of a 30 ps, $3\times 10^{18}$ W cm$^{-2}$ laser pulse with an underdense deuterium plasma has been observed up to 100 ps after the pulse propagation, when large numbers of post-solitons were seen to remain in the plasma. The temporal evolution of the post-solitons has been accurately characterized with a high spatial and temporal resolution. The observed expansion is compared to analytical models and three dimensional particle-in-cell results providing indication of the polarisation dependence of the post-soliton dynamics.