title: Attosecond electron bunches.
abstract: Electron bunches of attosecond duration may coherently interact with laser beams. We show how p-polarized ultraintense laser pulses interacting with sharp boundaries of overdense plasmas can produce such bunches. Particle-in-cell simulations demonstrate attosecond bunch generation during pulse propagation through a thin channel or in the course of grazing incidence on a plasma layer. In the plasma, due to the self-intersection of electron trajectories, electron concentration is abruptly peaked. A group of counterstream electrons is pushed away from the plasma through nulls in the electromagnetic field, having inherited a peaked electron density distribution and forming relativistic ultrashort bunches in vacuum.
authors.affiliation: Center for Ultrafast Optical Science and FOCUS Center, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors.forename: N
authors.initials: N
authors.lastname: Naumova
authors.forename: I
authors.initials: I
authors.lastname: Sokolov
authors.forename: J
authors.initials: J
authors.lastname: Nees
authors.forename: A
authors.initials: A
authors.lastname: Maksimchuk
authors.forename: V
authors.initials: V
authors.lastname: Yanovsky
authors.forename: G
authors.initials: G
authors.lastname: Mourou