Intrinsic channel closing in strong-field single ionization of H2

TL;DR

This study investigates how vibrational states influence electron spectra in strong-field ionization of H2, revealing that channel closings significantly affect ionization yields, with implications for understanding molecular responses to intense lasers.

Contribution

It introduces a vibrationally-resolved model for H2 ionization, demonstrating the impact of vibrational states on electron spectra and channel closing effects in molecules.

Findings

Vibrational quantum number affects electron spectra in H2 ionization.

Channel closings lead to enhanced electron yields at specific vibrational states.

Vibrational motion influences ionization dynamics in strong laser fields.

Abstract

The ionization of H2 in intense laser pulses is studied by numerical integration of the time-dependent Schr\"odinger equation for a single-active-electron model including the vibrational motion. The electron kinetic-energy spectra in high-order above-threshold ionization are strongly dependent on the vibrational quantum number of the created H2+ ion. For certain vibrational states, the electron yield in the mid-plateau region is strongly enhanced. The effect is attributed to channel closings, which were previously observed in atoms by varying the laser intensity.