Restricted-Geometry Quantum Models Beyond Atoms: Application of the Eckhardt-Sacha approach to NSDI in Diatomic Systems

TL;DR

This paper introduces a simplified quantum model for nonsequential double ionization in diatomic molecules under strong laser fields, extending atomic models to molecular systems and aligning well with experimental results.

Contribution

It extends the Eckhardt-Sacha restricted-geometry approach from atoms to diatomic molecules, providing a computationally efficient tool for molecular multi-electron dynamics.

Findings

Model captures the knee structure in ionization yields.

Good agreement with experimental data for $\sigma$-type orbitals.

Suitable for exploring complex molecular ionization processes.

Abstract

We present a (1+1)-dimensional quantum model designed to describe nonsequential double ionization (NSDI) in homonuclear diatomic molecules exposed to strong linearly polarized laser fields. Extending the restricted-geometry framework previously developed for atomic systems by Eckhardt and Sacha, our approach captures key features of NSDI, including the characteristic knee structure in double ionization yields. Despite its simplifying assumptions, the model shows good agreement with experimental data and proves particularly suitable for systems with $\sigma$-type orbital symmetry. It offers a computationally efficient tool for exploring multi-electron dynamics in molecular systems.