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

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 $\omega -2\omega$ 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.

7 pages

References in corpus (2)

• Electron spin polarization in strong-field ionization of Xenon atoms
• Time-resolved high harmonic spectroscopy of dynamical symmetry breaking in bi-circular laser fields

Cited by in corpus (1)

• Topological Floquet engineering using two frequencies in two dimensions