Dynamics of the Coulomb explosion of large clusters in a strong laser field

Abstract

The multielectron ionization and Coulomb explosion of ${\mathrm{Xe}}_{55},$ ${\mathrm{Xe}}_{249},$ ${\mathrm{Xe}}_{531},$ and ${\mathrm{Xe}}_{1061}$ clusters in a strong laser field is studied using classical dynamics simulations, which describe the motion of unbound electrons and ions. The generation of the unbound electrons is described as the removal of bound electrons from their host atoms (ions) by the electrostatic barrier suppression or collisional ionization. According to the results of simulations performed for the laser power ${10}^{16}{\mathrm{W}/\mathrm{c}\mathrm{m}}^{2}$ and frequency 0.386 ${\mathrm{fs}}^{\mathrm{\ensuremath{-}}1}$, almost all unbound electrons are removed from the clusters. In large ${\mathrm{Xe}}_{531}$ and ${\mathrm{Xe}}_{1061}$ clusters, electrons are removed mainly when the size of the clusters is enlarged due to Coulomb explosion. The quasiresonance energy enhancement is shown to be mainly responsible for the removal of electrons from the clusters. The energy enhancement process is hampered by electron-electron and electron-ion collisions.