Explosion of atomic clusters heated by high-intensity femtosecond laser pulses

Abstract

We have experimentally and theoretically studied the high-intensity $(>{10}^{16}{\mathrm{W}\mathrm{}\mathrm{cm}}^{\mathrm{\ensuremath{-}}2}),$ femtosecond photoionization of inertially confined noble-gas clusters. We have examined the energies of electrons and ions ejected during these interactions and found that particles with substantial kinetic energy are generated. Electrons with energies up to 3 keV and ions with energies of up to 1 MeV have been observed. These experimental observations are well explained by a theoretical model of the cluster as a small plasma sphere that explodes following rapid electron collisional heating by the intense laser pulse.