Eur. Phys. J. D 2, 143-147 (1998)
https://doi.org/10.1007/PL00021567

Azimuthal angular distributions for two-colour three-photon ionization of hydrogen

¹ Department of Chemistry, University of Bucharest, Bd. Carol 13, Bucharest, 70346 Romania
² Department of Physics, University of Bucharest, Bucharest-Magurele, 76900 Romania

Corresponding author: ^a flor@barutu.fizica.unibuc.ro

Received: 12 November 1997
Accepted: 23 February 1998
Published online: 13 August 2013

Abstract

We study in some detail the photoelectron angular distributions in two-colour three-photon ionization of the ground state hydrogen atom in its dependence on the polarizations of the two electromagnetic fields. We treat the particular case of photons propagating in the same direction and having elliptic polarizations with the same axes. The azimuthal distributions presented refer to the electrons emitted with momenta orthogonal to the photons direction. The calculations are done in nonrelativistic dipole approximation, in velocity gauge, using third-order perturbation theory. We show that the photoelectron azimuthal angular distributions have a fourfold symmetry only for identical linear or circular polarizations. In all the other cases the distribution has a twofold symmetry.