Excitation and Control of Plasma Wakefields by Multiple Laser Pulses

TL;DR

This paper demonstrates resonant plasma wave excitation using laser pulse trains and explores energy recovery techniques, advancing the development of controlled, high-repetition-rate laser-plasma accelerators.

Contribution

It provides the first experimental demonstration of resonant plasma wave excitation by multiple laser pulses and shows energy removal via an out-of-resonance pulse, supporting accelerator development.

Findings

Laser wakefields match analytical and numerical models.

Resonant excitation enhances plasma wave amplitude.

Energy can be extracted from wakefields using trailing pulses.

Abstract

We demonstrate experimentally the resonant excitation of plasma waves by trains of laser pulses. We also take an important first step to achieving an energy recovery plasma accelerator by showing that unused wakefield energy can be removed by an out-of-resonance trailing laser pulse. The measured laser wakefields are found to be in excellent agreement with analytical and numerical models of wakefield excitation in the linear regime. Our results indicate a promising direction for achieving highly controlled, GeV-scale laser-plasma accelerators operating at multi-kilohertz repetition rates. This article was published in Physical Review Letters 119, 044802 on 27 July 2017. DOI: 10.1103/PhysRevLett.119.044802 Copyright 2017 American Physical Society.