Eur. Phys. J. D 15, 33-39 (2001)
https://doi.org/10.1007/s100530170180

Ionization of a hydrogen atom from its ground state by a coherent bichromatic laser field

¹ Department of Chemistry, University of Bucharest, Bd. Regina Elisabeta 4-12, Bucharest 70346, Romania
² Institute of Space Sciences, P.O. Box MG-36, Bucharest-Magurele 76900, Romania

Corresponding author: ^a aurelia_cionga@yahoo.com or cionga@venus.nipne.ro

Received: 31 August 2000
Revised: 6 February 2001
Published online: 15 July 2001

Abstract

We study the "coherent phase control" between the three-photon ionization by a fundamental laser field and the one-photon ionization by its third harmonic for a hydrogen atom in its ground state. The relative phase of the harmonic field with respect to the fundamental laser radiation "modulates" the interference between the two ionization channels, which is important near the crossing points between the ionization rates of the two individual processes. Numerical results for the total ionization rate and for the angular distribution of the photoelectrons as a function of the phase are presented for frequencies located in the vicinity of the atomic resonances corresponding to the absorption of two laser photons.