title: Electron acceleration driven by ultrashort and nonparaxial radially polarized laser pulses.
abstract: Exact closed-form solutions to Maxwell's equations are used to investigate the acceleration of electrons in vacuum driven by ultrashort and nonparaxial radially polarized laser pulses. We show that the threshold power above which significant acceleration takes place is greatly reduced by using a tighter focus. Moreover, electrons accelerated by tightly focused single-cycle laser pulses may reach around 80% of the theoretical energy gain limit, about twice the value previously reported with few-cycle paraxial pulses. Our results demonstrate that the direct acceleration of electrons in vacuum is well within reach of current laser technology.
authors: Centre d’Optique, Photonique et Laser, Université Laval 2375 Rue de la Terrasse, Québec, Québec G1V0A6, Canada. vincent.marceau.2@ulaval.ca
authors: Vincent
authors: V
authors: Marceau
authors: Alexandre
authors: A
authors: April
authors: Michel
authors: M
authors: Piché