Vacuum laser acceleration of relativistic electrons using plasma mirror injectors

TL;DR

This paper demonstrates the first experimental realization of vacuum laser acceleration of relativistic electrons using plasma mirror injectors, enabling efficient electron acceleration in ultraintense laser fields.

Contribution

It introduces a novel plasma mirror injection method that overcomes previous experimental challenges in vacuum laser acceleration.

Findings

Successful experimental evidence of vacuum laser acceleration

Use of plasma mirror injectors for electron injection

Potential for high-charge, ultrashort relativistic electron beams

Abstract

Accelerating particles to relativistic energies over very short distances using lasers has been a long standing goal in physics. Among the various schemes proposed for electrons, vacuum laser acceleration has attracted considerable interest and has been extensively studied theoretically because of its appealing simplicity: electrons interact with an intense laser field in vacuum and can be continuously accelerated, provided they remain at a given phase of the field until they escape the laser beam. But demonstrating this effect experimentally has proved extremely challenging, as it imposes stringent requirements on the conditions of injection of electrons in the laser field. Here, we solve this long-standing experimental problem for the first time by using a plasma mirror to inject electrons in an ultraintense laser field, and obtain clear evidence of vacuum laser acceleration. With the advent of PetaWatt class lasers, this scheme could provide a competitive source of very high charge (nC) and ultrashort relativistic electron beams.