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arXiv · 2203.04839

Evidence of ac-Stark-shifted resonances in intense two-color circularly polarized laser fields

Philipp Stammer·Serguei Patchkovskii·Felipe Morales
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Abstract

We report on the appearance of a structure at low energies in the photo-electron momentum distribution of the hydrogen atom exposed to two-color counter-rotating bi-circular laser fields. These structures, which arise due to AC-Stark shifted resonances, break the three-fold symmetry, typical for the $ω-2ω$ bi-circular fields. We discuss the physical origin of this structure in terms of partial-wave interference between direct ionization channels and a resonant pathway, that passes through the AC-Stark shifted state and show how the underlying Rydberg state population depend on the field strength and pulse duration.

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Philipp Stammer, Serguei Patchkovskii, Felipe Morales. 2022-03-09. Evidence of ac-Stark-shifted resonances in intense two-color circularly polarized laser fields. https://doi.org/10.1103/physreva.101.033405

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