Teravolt-per-meter plasma wakefields from low-charge, femtosecond electron beams

TL;DR

This paper explores the use of ultra-short, low-charge electron beams to generate extremely high plasma wakefields exceeding 1 TV/m, enabling new regimes in high-field atomic physics and frontier experiments.

Contribution

It demonstrates a focusing scheme to produce nanometer-scale beams capable of exciting unprecedented plasma wakefield strengths, advancing ultra-fast electron beam applications.

Findings

Achieved plasma wakefields exceeding 1 TV/m.

Developed a focusing scheme for ~200 nm beam sizes.

Enabled sub-fs plasma formation for wake excitation.

Abstract

Recent initiatives in ultra-short, GeV electron beam generation have focused on achieving sub-fs pulses for driving X-ray free-electron lasers (FELs) in single-spike mode. This scheme employs very low charge beams, which may allow existing FEL injectors to produce few-100 as pulses, with high brightness. Towards this end, recent experiments at SLAC have produced ~2 fs rms, low transverse emittance, 20 pC electron pulses. Here we examine use of such pulses to excite plasma wakefields exceeding 1 TV/m. We present a focusing scheme capable of producing ~200 nm beam sizes, where the surface Coulomb fields are also ~TV/m. These conditions access a new regime for high field atomic physics, allowing frontier experiments, including sub-fs plasma formation for wake excitation.