Self-truncated ionization injection and consequent monoenergetic electron bunches in laser wakefield acceleration

Zeng, Ming and Chen, Min and Sheng, Zheng-Ming and Mori, Warren B. and Zhang, Jie (2014) Self-truncated ionization injection and consequent monoenergetic electron bunches in laser wakefield acceleration. Physics of Plasmas, 21 (3). 030701. ISSN 1070-664X (https://doi.org/10.1063/1.4868404)

[thumbnail of Zeng-etal-PP2014-self-truncated-ionization-injection-monoenergetic-electron]
Preview
PDF. Filename: Zeng_etal_PP2014_self_truncated_ionization_injection_monoenergetic_electron.pdf
Accepted Author Manuscript
License: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 logo

Download (402kB)| Preview

Abstract

The ionization-induced injection in laser wakefield acceleration has been recently demonstrated to be a promising injection scheme. However, the energy spread controlling in this mechanism remains a challenge because continuous injection in a mixed gas target is usually inevitable. Here, we propose that by use of certain initially unmatched laser pulses, the electron injection can be constrained to the very front region of the mixed gas target, typically in a length of a few hundreds micrometers determined by the laser self-focusing and the wake deformation. As a result, the produced electron beam has narrow energy spread and meanwhile contains tens of pC in charge. Both multidimensional simulations and theoretical analysis illustrate the effectiveness of this scheme.