Optical Modulation of Electron Beams in Free Space

TL;DR

This paper demonstrates how tailored optical fields can be used to manipulate electron beams in free space, enabling correction of aberrations and shaping of focal profiles with currently available ultrafast electron microscopes.

Contribution

It introduces a novel method for free-space optical manipulation of electron beams using stimulated elastic Compton scattering, supported by a rigorous semiclassical quantum theory.

Findings

Optical fields can correct electron beam aberrations.

Phase imprinting is achieved via stimulated elastic Compton scattering.

Method is feasible with existing ultrafast electron microscope technology.

Abstract

We exploit free-space interactions between electron beams and tailored light fields to imprint on-demand phase profiles on the electron wave functions. Through rigorous semiclassical theory involving a quantum description of the electrons, we show that monochromatic optical fields focused in vacuum can be used to correct electron beam aberrations and produce selected focal shapes. Stimulated elastic Compton scattering is exploited to imprint the phase, which is proportional to the integrated optical field intensity along the electron path and depends on the transverse beam position. The required light intensities are attainable in currently available ultrafast electron microscope setups, thus opening the field of free-space optical manipulation of electron beams.