Inelastic electron-vortex-beam scattering

TL;DR

This paper develops a theoretical framework for inelastic scattering of electron vortex beams, revealing how orbital angular momentum transfer occurs and how vortex beams can be used to probe atomic and magnetic properties.

Contribution

It introduces an analytical model for inelastic scattering of vortex beams, clarifying momentum transfer mechanisms and their applications in atomic excitation and magnetic transition detection.

Findings

OAM transfer occurs via pre- and post-selection, not selective excitation.

Vortex beams can be used to detect magnetic transitions.

The model provides insights into scattering processes involving vortex beams.

Abstract

Recent theoretical and experimental developments in the field of electron vortex beam physics have raised questions on what exactly this novelty in the field of electron microscopy (and other fields, such as particle physics) really provides. An important part in the answer to those questions lies in scattering theory. The present investigation explores various aspects of inelastic quantum scattering theory for cylindrically symmetric beams with orbital angular momentum. The model system of Coulomb scattering on a hydrogen atom provides the setting to address various open questions: How is momentum transferred? Do vortex beams selectively excite atoms, and how can one employ vortex beams to detect magnetic transitions? The analytical approach presented here provides answers to these questions. OAM transfer is possible, but not through selective excitation; rather, by pre- and post-selection one can filter out the relevant contributions to a specific signal.