title: Generation of quasimonoenergetic electron bunches with 80-fs laser pulses.
abstract: Highly collimated, quasimonoenergetic multi-MeV electron bunches were generated by the interaction of tightly focused, 80-fs laser pulses in a high-pressure gas jet. These monoenergetic bunches are characteristic of wakefield acceleration in the highly nonlinear wave breaking regime, which was previously thought to be accessible only by much shorter laser pulses in thinner plasmas. In our experiment, the initially long laser pulse was modified in underdense plasma to match the necessary conditions. This picture is confirmed by semianalytical scaling laws and 3D particle-in-cell simulations. Our results show that laser-plasma interaction can drive itself towards this type of laser wakefield acceleration even if the initial laser and plasma parameters are outside the required regime.
authors.affiliation: Institut für Laser- und Plasmaphysik, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Hidding
authors.forename: K-U
authors.initials: KU
authors.lastname: Amthor
authors.forename: B
authors.initials: B
authors.lastname: Liesfeld
authors.forename: H
authors.initials: H
authors.lastname: Schwoerer
authors.forename: S
authors.initials: S
authors.lastname: Karsch
authors.forename: M
authors.initials: M
authors.lastname: Geissler
authors.forename: L
authors.initials: L
authors.lastname: Veisz
authors.forename: K
authors.initials: K
authors.lastname: Schmid
authors.forename: J G
authors.initials: JG
authors.lastname: Gallacher
authors.forename: S P
authors.initials: SP
authors.lastname: Jamison
authors.forename: D
authors.initials: D
authors.lastname: Jaroszynski
authors.forename: G
authors.initials: G
authors.lastname: Pretzler
authors.forename: R
authors.initials: R
authors.lastname: Sauerbrey