Strong-Field Nonsequential Double Photoionization Using Virtual Detector Theory with Path Summation

TL;DR

This paper extends virtual detector theory to analyze nonsequential double ionization in a two-electron atom under strong laser fields, providing detailed insights into ionization pathways and electron dynamics through path summation and virtual particle tracking.

Contribution

It introduces a novel application of virtual detector theory with path summation to model multi-electron strong-field ionization dynamics, including double photoelectron momentum distributions.

Findings

Double photoelectron momentum distribution calculated via path summation.

Identification of different ionization and recollision pathways.

Demonstrates the importance of quantum phase evolution in electron propagation.

Abstract

We present an ab initio study of the nonsequential strong-field ionization dynamics of a model two-electron atom with helium character. Single- and double-ionization events are characterized and displayed using detector signals extracted at different points in the two-electron two-dimensional space. The double photoelectron momentum distribution is calculated via coherent path-summation over virtual particle trajectories. Insights into different ionization and electron recollision pathways are gained from detailed virtual-particle tracking and energy-time readouts. This study demonstrates the extension of virtual detector theory to strong-field multi-electron quantum dynamics and highlights the importance of the evolving quantum phase in quasi-classical electron propagation.