Demonstration of relativistic electron beam focusing by a laser-plasma lens

TL;DR

This paper demonstrates that a laser-plasma lens can significantly reduce the divergence of relativistic electron beams, enabling more efficient transport and potential applications in compact accelerators and ultrafast science.

Contribution

It introduces and experimentally validates a laser-plasma lens capable of focusing high-current relativistic electron beams with unprecedented field gradients.

Findings

Reduced electron beam divergence by nearly a factor of three

Field gradients five orders of magnitude larger than conventional optics

Potential for improved beam transport in compact accelerators

Abstract

Laser-plasma technology promises a drastic reduction of the size of high energy electron accelerators. It could make free electron lasers available to a broad scientific community, and push further the limits of electron accelerators for high energy physics. Furthermore the unique femtosecond nature of the source makes it a promising tool for the study of ultra-fast phenomena. However, applications are hindered by the lack of suitable lens to transport this kind of high-current electron beams, mainly due to their divergence. Here we show that this issue can be solved by using a laser-plasma lens, in which the field gradients are five order of magnitude larger than in conventional optics. We demonstrate a reduction of the divergence by nearly a factor of three, which should allow for an efficient coupling of the beam with a conventional beam transport line.