Multiple Ionization Bursts in Laser-Driven Hydrogen Molecular Ion

TL;DR

This paper reveals that hydrogen molecular ions exhibit multiple ionization bursts within a laser cycle due to transient electron localization, challenging the traditional tunnel ionization model for atoms.

Contribution

It introduces a theoretical framework showing multiple ionization bursts in H₂⁺ caused by electron localization, with a proposed experimental probing method.

Findings

Multiple ionization bursts occur within a half-cycle.

Electron localization at nuclei induces ionization bursts.

Relation between localization timing and laser vector potential.

Abstract

Theoretical study on H$_2^+$ in an intense infrared laser field on the attosecond time-scale reveals that the molecular ion shows multiple bursts of ionization within a half-cycle of the laser field oscillation, in contrast to the widely accepted tunnel ionization picture for an atom. These bursts are found to be induced by transient localization of the electron at one of the nuclei, and a relation between the time instants of the localization and the vector potential of the laser light is derived. Furthermore, an experimental scheme is proposed to probe the localization dynamics by an extreme ultraviolet laser pulse.