Polarization Effects in Laser-Assisted (e,2e) Collision on H-atom by Twisted Electrons

TL;DR

This study investigates how laser polarization affects (e,2e) collision cross-sections on hydrogen atoms impacted by twisted electrons, revealing larger cross-sections for circular polarization and sensitivity to orbital angular momentum superpositions.

Contribution

It introduces a formalism for analyzing laser-assisted (e,2e) collisions with twisted electrons, highlighting polarization and OAM effects on differential cross-sections.

Findings

Circular polarization yields larger cross-sections than linear polarization.

Angular distributions of TDCS differ notably between polarization types.

TDCS is highly sensitive to OAM differences and phase in superpositions.

Abstract

The dynamics of fast (e, 2e) collisions, induced by the impact of twisted electron beams, on atomic hydrogen, is analyzed in the presence of a laser field with circular and linear polarization. For the (e,2e) differential cross-section calculations we use Volkov and Coulomb-Volkov wave functions for scattered and ejected electrons, respectively, while the laser-atom interaction is treated in first-order perturbation theory. The formalism is developed for the asymmetric coplanar geometry in the first Born approximation. We investigate the influence of laser field polarization and provide a comparative analysis of Triple Differential Cross-Sections (TDCS) for circularly and linearly polarized laser fields as a function of ejected electron angle. The overall magnitude of the cross-section is larger for circular polarization as compared to linear polarization. Some notable changes in the angular distributions of TDCS were also observed for the circular polarization as compared to that for linear polarization. We further extend the study to coherent superpositions of twisted electron beams to examine OAM effects for macroscopic target which shows that the TDCS$_{av}$ is strongly sensitive to the difference of the projectiles OAM as well as on the phase difference between them.