Nonlinear Laser Driven Donut Wakefields for Positron and Electron Acceleration

Abstract

We show analytically and through three-dimensional particle-in-cell simulations that nonlinear wakefields driven by Laguerre-Gaussian laser pulses can lead to hollow electron self-injection and positron acceleration. We find that higher order lasers can drive donut shaped blowout wakefields with strong positron accelerating gradients comparable to those of a spherical bubble. Corresponding positron focusing forces can be more than an order of magnitude stronger than electron focusing forces in a spherical bubble. Required laser intensities and energies to reach the nonlinear donut shaped blowout are within state-of-the-art experimental conditions.DOI: http://dx.doi.org/10.1103/PhysRevLett.112.215001Published 27 May 2014Received 5 February 2014© 2014 American Physical Society