Multielectron effect in XUV light-driven strong-field ionization beyond the dipole approximation

Abstract

By applying the time-dependent density-functional theory, we theoretically investigate the multielectron effect in the extreme UV (XUV) light-driven ionization of atoms and diatomic molecules beyond the dipole approximation. Compared to the theoretical results obtained in the single active electron approximation, the multielectron effect leads to more tilted photoelectron angular momentum distributions (PADs) toward the light propagation direction. According to our analysis, this might be due to photon momentum sharing between multiple electrons. Furthermore, we study the multielectron effect on the birth time delay phenomenon in the ionization of a hydrogen molecule. By extracting the interference minima of the PADs, we demonstrate that the birth time delay is hardly affected by the multielectron effect. The present work provides a better understanding of the association between the nondipole effect and the multielectron effect.