Few-femtosecond Electron Beam with THz-frequency Wakefield-driven Compression

TL;DR

This paper introduces a novel passive method to produce few-femtosecond electron beams using THz-frequency wakefields, achieving significant compression with low timing jitter, beneficial for ultrafast applications.

Contribution

The paper presents a new passive bunching technique utilizing THz wakefields in a dielectric tube for ultrashort electron beam generation with minimal timing jitter.

Findings

Electron beams compressed from 150 fs to about 7 fs (rms).

No additional timing jitter introduced during compression.

Potential applications in ultrafast electron diffraction and plasma acceleration.

Abstract

We propose and demonstrate a novel method to produce few-femtosecond electron beam with relatively low timing jitter. In this method a relativistic electron beam is compressed from about 150 fs (rms) to about 7 fs (rms, upper limit) with the wakefield at THz frequency produced by a leading drive beam in a dielectric tube. By imprinting the energy chirp in a passive way, we demonstrate through laser-driven THz streaking technique that no additional timing jitter with respect to an external laser is introduced in this bunch compression process, a prominent advantage over the conventional method using radio-frequency bunchers. We expect that this passive bunching technique may enable new opportunities in many ultrashort-beam based advanced applications such as ultrafast electron diffraction and plasma wakefield acceleration.