Quantum-quasiclassical analysis of center-of-mass nonseparability in hydrogen atom stimulated by strong laser fields

TL;DR

This paper introduces a quantum-quasiclassical computational method to analyze the coupled quantum and classical dynamics of a hydrogen atom in strong laser fields, revealing how center-of-mass measurements can infer electron quantum behavior.

Contribution

The paper presents a novel quantum-quasiclassical scheme for simulating nonseparable electron and center-of-mass dynamics in strong laser fields, linking classical measurements to quantum electron dynamics.

Findings

Strong correlation between CM kinetic energy and electron spectral density.

CM velocity spectroscopy can detect internal electron quantum dynamics.

Method applicable to analyzing relativistic effects in laser-atom interactions.

Abstract

We have developed a quantum-quasiclassical computational scheme for quantitative treating of the nonseparable quantum-classical dynamics of the 6D hydrogen atom in a strong laser pulse. In this approach, the electron is treated quantum mechanically and the center-of-mass (CM) motion classically. Thus, the Schr\"odinger equation for the electron and the classical Hamilton equations for the CM variables, nonseparable due to relativistic effects stimulated by strong laser fields, are integrated simultaneously. In this approach, it is natural to investigate the idea of using the CM-velocity spectroscopy as a classical ``build-up'' set up for detecting the internal electron quantum dynamics. We have performed such an analysis using the hydrogen atom in linearly polarized laser fields as an example and found a strong correlation between the CM kinetic energy distribution after a laser pulse and the spectral density of electron kinetic energy. This shows that it is possible to detect the quantum dynamics of an electron by measuring the distribution of the CM kinetic energy.