Formation and evolution of post-solitons following a high intensity laser-plasma interaction with a low-density foam target
Abstract

The formation and evolution of post-solitons has been discussed for quite some time both analytically and through the use of particle-in-cell (PIC) codes. It is however only recently that they have been directly observed in laser-plasma experiments. Relativistic electromagnetic (EM) solitons are localised structures that can occur in collisionless plasmas. They consist of a low-frequency EM wave trapped in a low electron number-density cavity surrounded by a shell with a higher electron number-density. Here we describe the results of an experiment in which a 100 TW Ti:sapphire laser (30 fs, 800 nm) irradiates a$0.03 gcm−3$TMPTA foam target with a focused intensity$Il=9.5×1017 Wcm−2$. A third harmonic ($λprobe≃266$nm) probe is employed to diagnose plasma motion for 25 ps after the main pulse interaction via Doppler-Spectroscopy. Both radiation-hydrodynamics and 2D PIC simulations are performed to aid in the interpretation of the experimental results. We show that the rapid motion of the probe critical-surface observed in the experiment might be a signature of post-soliton wall motion.

Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10362639
Journal Name:
Plasma Physics and Controlled Fusion
Volume:
63
Issue:
7
Page Range or eLocation-ID:
Article No. 074001
ISSN:
0741-3335
Publisher:
IOP Publishing
National Science Foundation
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