Low-Energy Electron Emission in the Strong-Field Ionization of Rare Gas Clusters

Abstract

Clusters and nanoparticles have been widely investigated to determine how plasmonic near fields influence the strong-field induced energetic electron emission from finite systems. We focus on the contrary, i.e., the slow electrons, and discuss a hitherto unidentified low-energy structure (LES) in the photoemission spectra of rare gas clusters in intense near-infrared laser pulses. For Ar and Kr clusters we find, besides field-driven fast electrons, a robust and nearly isotropic emission of electrons with <4 eV kinetic energies that dominates the total yield. Molecular dynamics simulations reveal a correlated few-body decay process involving quasifree electrons and multiply excited ions in the nonequilibrium nanoplasma that results in a dominant LES feature. Our results indicate that the LES emission occurs after significant nanoplasma expansion, and that it is a generic phenomenon in intense laser nanoparticle interactions, which is likely to influence the formation of highly charged ions.

Suppression of thermal nanoplasma emission in clusters strongly ionized by hard x-rays

“…ICD-like, autoionization or CED) processes involving high-lying Rydberg states, similarly to the classical treatment in Ref. [52,53]. However, we also note that correlated processes which involve both classically treated electrons and quantum-modelled states (e.g.…”

Laser-Induced Electron Transfer in the Dissociative Multiple Ionization of Argon Dimers

“…vdW dimers are used to study photoinduced biological processes [12][13][14], photocatalytic reactions [15,16], and energy or charge transfer reactions induced by soft x-ray photons [17][18][19][20] and electron impact [21]. vdW systems are also studied with strong laser fields, but in the case of dimers with a focus on the field-driven ionization and fragmentation dynamics [22][23][24][25][26][27][28][29][30][31][32][33][34][35], or electronic energy conversion processes in the case of larger clusters [36][37][38][39][40][41]. To the best of our knowledge, strong-field driven electron transfer reactions across the system boundary from one entity to another have not been investigated, thus far.…”

Low-Energy Protons in Strong-Field Dissociation of H 2 + via Dipole-Transitions at Large Bond Lengths

“…In ultrafast physics, the energy spectrum of electrons or nuclei is overwhelmingly crucial since it is the knob to retrieve atomic or molecular ultrafast dynamics. For example, the low-energy structure in the photoelectron energy spectrum [1,2], regarded as an "ionization surprise" [3], has been used to unveil the importance of the field-driven rescattering in the long-range Coulomb potential [2,[4][5][6][7][8][9][10]. For molecules in intense laser fields, different dissociation pathways contribute to different nuclear fragment energies.…”