High-order above-threshold ionization of an atom in intense quantum light
Shijun Wang, XuanYang Lai
Abstract
We investigate high-order above-threshold ionization (HATI) from intense quantum light-atom interaction, by numerically solving the fully quantum time-dependent Schr\"odinger equation based on quantum electrodynamics theory. Our simulations show that, in comparison with coherent-state (classical) light, the HATI spectra from intense quantum lights may have a higher cutoff energy and, moreover, for a given ponderomotive energy of the laser field, the cutoff energy is dependent on the laser wavelength and the ionization potential of the atom. The influence of quantum light on the HATI is revealed by examining the interplay between a quasiprobability distribution of the electric field of the quantum light and the Ammosov-Delone-Krainov ionization rate of the atom. Furthermore, analytical formulas of the cutoff energy of the HATI spectra for different quantum lights are derived.