Multiple electron trapping in the fragmentation of strongly driven molecules

TL;DR

This study uses a theoretical quasiclassical approach to explore how two highly excited neutral hydrogen atoms form during the Coulomb explosion of strongly driven H$_2$, emphasizing the importance of two-electron effects.

Contribution

It reveals the pathway and mechanisms for double H$^{*}$ formation, highlighting the role of two-electron effects and frustrated ionization steps in the process.

Findings

Double H$^{*}$ formation involves both ionization steps being frustrated.

Two-electron effects are crucial for accurate modeling.

The pathway resembles a known single H$^{*}$ formation route, but with key differences.

Abstract

We present a theoretical quasiclassical study of the formation, during Coulomb explosion, of two highly excited neutral H atoms (double H$^{*}$) of strongly driven H$_2$. In this process, after the laser field is turned off each electron occupies a Rydberg state of an H atom. We show that two-electron effects are important in order to correctly account for double H$^{*}$ formation. We find that the route to forming two H$^{*}$ atoms is similar to pathway B that was identified in Phys. Rev. A {\bf 85} 011402 (R) as one of the two routes leading to single H$^{*}$ formation. However, instead of one ionization step being "frustrated" as is the case for pathway B, both ionization steps are "frustrated" in double H$^{*}$ formation. Moreover, we compute the screened nuclear charge that drives the explosion of the nuclei during double H$^{*}$ formation.