Attosecond Control of Electron Beams at Dielectric and Absorbing Membranes

TL;DR

This paper demonstrates experimental and theoretical methods for generating and controlling attosecond electron pulses using dielectric and absorbing membranes, optimizing conditions for ultrafast electron beam manipulation across different wavelengths.

Contribution

It introduces a comprehensive study of electron pulse control via optical fields at membranes, highlighting the optimal materials and conditions for attosecond pulse generation.

Findings

Dielectric membranes are ideal for visible/near-infrared regimes.

Metallic membranes are optimal for mid-infrared and terahertz wavelengths.

Electric and magnetic fields both significantly influence electron control.

Abstract

Ultrashort electron pulses are crucial for time-resolved electron diffraction and microscopy of fundamental light-matter interaction. In this work, we study experimentally and theoretically the generation and characterization of attosecond electron pulses by optical-field-driven compression and streaking at dielectric or absorbing interaction elements. The achievable acceleration and deflection gradient depends on the laser-electron angle, the laser's electric and magnetic field directions and the foil orientation. Electric and magnetic fields have similar contributions to the final effect and both need to be considered. Experiments and theory agree well and reveal the optimum conditions for highly efficient, velocity-matched electron-field interactions in longitudinal or transverse direction. We find that metallic membranes are optimum for light-electron control at mid-infrared or terahertz wavelengths, but dielectric membranes are excel in the visible/near-infrared regimes and are therefore ideal for the formation of attosecond electron pulses.