Influence of Coulomb potential on photoelectron momentum distributions in few-cycle linearly polarized laser field

Abstract

We investigate the influence of the Coulomb potential on the photoelectron momentum distributions of H atoms in few-cycle linearly polarized laser field by numerically solving the time-dependent Schrödinger equation and using the semi-classical method. We demonstrate that the electrons ionized from the different time windows will contribute to different interference types and regions in the photoelectron momentum distributions. The typical trajectories of the photoelectrons are used to illustrate the effect of the Coulomb potential on the interference stripes. We mainly investigate the photoelectron momentum distribution contributed by the electron wave packets, which are emitted within the nonadjacent falling edges of the electric field. In this case, a discontinuous region near the center of the photoelectron momentum distribution can be clearly observed, which exhibits a strong dependence on the Coulomb potential. We also observe a shift in the photoelectron momentum distributions in each quarter cycle. We quantitatively illustrate that the shift is induced by the Coulomb correction along the axis of polarization. Our results may provide a reference for further analytical research about the shift of the photoelectron momentum distributions in few-cycle strong laser field.