Optical control of electron phase space in plasma accelerators with incoherently stacked laser pulses

Authors

Serguei Y. Kalmuykov, University of Nebraska-LincolnFollow
X Davoine, CEA
R Lehe, ENTA-CNRS-Ecole Polytechnique
A F. Lifschitz, ENTA-CNRS-Ecole Polytechnique
Bradley Allan Shadwick, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2015

Citation

PHYSICS OF PLASMAS 22, 056701 (2015)

Comments

Copyright 2015 Used by permission

Abstract

It is demonstrated that synthesizing an ultrahigh-bandwidth, negatively chirped laser pulse by incoherently stacking pulses of different wavelengths makes it possible to optimize the process of electron self-injection in a dense, highly dispersive plasma (n0 ~ 1019 c~3). Avoiding transformation of the driving pulse into a relativistic optical shock maintains a quasi-monoenergetic electron spectrum through electron dephasing and boosts electron energy far beyond the limits suggested by existing scaling laws. In addition, evolution of the accelerating bucket in a plasma channel is shown to produce a background-free, tunable train of femtosecond-duration, 35–100 kA, time-synchronized quasi-monoenergetic electron bunches. The combination of the negative chirp and the channel permits acceleration of electrons beyond 1 GeV in a 3mm plasma with 1.4 J of laser pulse energy, thus offering the opportunity of high-repetition-rate operation at manageable average laser power.