R-matrix-Floquet theory of multiphoton processes. III. Multiphoton ionization of atomic hydrogen

Abstract

Using the recently proposed R-mafrix-Floquel theory we have analysed lhe multiphoion ionization of atomic hydrogen from the gmund stale and the metastable 2s state in an intense, linearly polarized and monochromatic laser field.Results are presented for total ionization rates, branching ratios into photon absorption channels (including ATL above threshold ionization) and angular disuibutions, for several frequencies and a range of laser intensities.We also discuss the limits of lowest order perturbation theory and we sNdy high-frequency stabilization a[ high intensities.