Semiclassical two-step model for ionization of hydrogen molecule by strong laser field

TL;DR

This paper extends a semiclassical model to hydrogen molecules, revealing significant differences in ionization patterns compared to atomic hydrogen, including altered energy spectra and interference fringes under strong laser fields.

Contribution

The authors develop a semiclassical two-step model for hydrogen molecules that incorporates quantum interference and Coulomb effects beyond perturbation theory.

Findings

Hydrogen molecule ionization spectra decay slower at high energies.

Holographic interference fringes are more prominent in molecules than atoms.

Significant deviations in photoelectron momentum distributions are observed.

Abstract

We extend the semiclassical two-step model for strong-field ionization that describes quantum interference and accounts for the Coulomb potential beyond the semiclassical perturbation theory to the hydrogen molecule. In the simplest case of the molecule oriented along the polarization direction of a linearly polarized laser field, we predict significant deviations of the two-dimensional photoelectron momentum distributions and the energy spectra from the case of atomic hydrogen. Specifically, for the hydrogen molecule the electron energy spectrum falls off slower with increasing energy, and the holographic interference fringes are more pronounced than for the hydrogen atom at the same parameters of the laser pulse.