Pathways to double ionization of atoms in strong fields
Abstract
We discuss the final stages of double ionization of atoms in a strong linearly polarized laser field within a classical model. We propose that all trajectories leading to non-sequential double ionization pass close to a saddle in phase space which we identify and characterize. The saddle lies in a two degree of freedom subspace of symmetrically escaping electrons. The distribution of longitudinal momenta of ions as calculated within the subspace shows the double hump structure observed in experiments. Including a symmetric bending mode of the electrons allows us to reproduce the transverse ion momenta. We discuss also a path to sequential ionization and show that it does not lead to the observed momentum distributions.
Cite
@article{arxiv.physics/0010031,
title = {Pathways to double ionization of atoms in strong fields},
author = {Krzysztof Sacha and Bruno Eckhardt},
journal= {arXiv preprint arXiv:physics/0010031},
year = {2009}
}
Comments
10 pages, 10 figures; fig.6 and 7 exchanged in the final version accepted for publication in Phys. Rev. A