Low transverse emittance electron bunches from two-color laser-ionization injection
Abstract
A method is proposed to generate low emittance electron bunches from two color laser pulses in a laser-plasma accelerator. A two-region gas structure is used, containing a short region of a high-Z gas (e.g., krypton) for ionization injection, followed by a longer region of a low-Z gas for post-acceleration. A long-laser-wavelength (e.g., 5 micron) pump pulse excites plasma wake without triggering the inner-shell electron ionization of the high-Z gas due to low electric fields. A short-laser-wavelength (e.g., 0.4 micron) injection pulse, located at a trapping phase of the wake, ionizes the inner-shell electrons of the high-Z gas, resulting in ionization-induced trapping. Compared with a single-pulse ionization injection, this scheme offers an order of magnitude smaller residual transverse momentum of the electron bunch, which is a result of the smaller vector potential amplitude of the injection pulse.
Cite
@article{arxiv.1305.4149,
title = {Low transverse emittance electron bunches from two-color laser-ionization injection},
author = {Lu-Le Yu and Eric Esarey and Jean-Luc Vay and Carl B. Schroeder and Carlo Benedetti and Cameron G. R. Geddes and Sergey G. Rykovanov and Stepan S. Bulanov and Min Chen and Wim P. Leemans},
journal= {arXiv preprint arXiv:1305.4149},
year = {2015}
}