Anisotropic field ionization in nano-clusters mediated by Brunel-electron driven plasma waves
Abstract
Ionization is one of the most fundamental processes in intense laser-matter interaction. It is extremely efficient for clusters in laser fields and often leads to surprisingly high charge states at moderate laser intensities. Here we reveal a novel ionization mechanism in laser-cluster interaction through particle-in-cell simulations. As the laser field ionizes a cluster, Brunel electrons pushed back into the clustered plasma form an attosecond bunches, impulsively exciting plasma oscillation. The resulting localized wake field further ionizes the cluster, causing a highly ionized rod-like core along the polarization axis. This anisotropic ionization is prominent using few-cycle pulses and may be washed out using longer pulses due to collisional ionization. This newly identified ionization channel can potentially provide complicated site-specific control of ionization in nanometer-scale targets.
Cite
@article{arxiv.2304.02876,
title = {Anisotropic field ionization in nano-clusters mediated by Brunel-electron driven plasma waves},
author = {Xiaohui Gao},
journal= {arXiv preprint arXiv:2304.02876},
year = {2023}
}