A novel vortex generator and mode converter for electrons

TL;DR

This paper introduces a new vortex generator and mode converter for electron beams, enabling transformation, discrimination, and high-brilliance generation of vortex modes with potential applications in electron microscopy.

Contribution

It presents a novel mode converter for electron vortex beams, validated by simulations and experiments, that can transform, discriminate, and generate high-brilliance vortex modes.

Findings

Converter transforms $m=\pm 1$ beams into Hermite-Gaussian modes

Experimental confirmation of simulation results

Enables high-brilliance electron vortex beam generation

Abstract

A mode converter for electron vortex beams is described. Numerical simulations, confirmed by experiment, show that the converter transforms a vortex beam with topological charge $m=\pm 1$ into beams closely resembling Hermite-Gaussian HG$_{10}$ and HG$_{01}$ modes. The converter can be used as a mode discriminator or filter for electron vortex beams. Combining the converter with a phase plate turns a plane wave into modes with topological charge $m=\pm 1$. This combination serves as a generator of electron vortex beams of high brilliance.