Non-adiabatic imprints on the low-energy structure in above-threshold ionization

Abstract

Abstract We experimentally investigate the energy-resolved angular distributions (ADs) of low-energy photoelectrons from above-threshold ionization (ATI) of Xe in intense infrared laser fields. An unexpected wavelength dependence of ADs for the low-energy structure (LES), in striking contrast to the prediction of the Coulomb-corrected semiclassical model, has been found. By improving the semiclassical model with non-adiabatic corrections, the experimental features can be qualitatively reproduced, and we suggest the indispensable role of the non-adiabatic effect in producing the LES. Our finding provides new insights into the understanding of low-energy electron dynamics of atoms with intense laser fields.