Dense attosecond electron sheets from laser wakefields using an up-ramp density transition

Li, F.Y. and Sheng, Z.M. and Liu, Y. and Meyer-ter-Vehn, J. and Mori, W.B. and Lu, W. and Zhang, J. (2013) Dense attosecond electron sheets from laser wakefields using an up-ramp density transition. Physical Review Letters, 110 (13). 135002. ISSN 0031-9007

[img]
Preview
Text (Li-etal-PRL-2015-Dense-attosecond-electron-sheets-from-laser-wakefields-using-an-up-ramp)
Li_etal_PRL_2015_Dense_attosecond_electron_sheets_from_laser_wakefields_using_an_up_ramp.pdf
Accepted Author Manuscript

Download (6MB)| Preview

    Abstract

    Controlled electron injection into a laser-driven wakefield at a well defined space and time is reported based on particle-in-cell simulations. Key novel ingredients are an underdense plasma target with an up-ramp density profile followed by a plateau and a fairly large laser focus diameter that leads to an essentially one-dimensional (1D) regime of laser wakefield, which is different from the bubble (complete blowout) regime occurring for tightly focused drive beams. The up-ramp profile causes 1D wave breaking to occur sharply at the up-ramp-plateau transition. As a result, it generates an ultrathin (few nanometer, corresponding to attosecond duration), strongly overdense relativistic electron sheet that is injected and accelerated in the wakefield. A peaked electron energy spectrum and high charge (∼nC) distinguish the final sheet.