title: Quasimonoenergetic proton bunch generation by dual-peaked electrostatic-field acceleration in foils irradiated by an intense linearly polarized laser.
abstract: It is found that stable proton acceleration from a thin foil irradiated by a linearly polarized ultraintense laser can be realized for appropriate foil thickness and laser intensity. A dual-peaked electrostatic field, originating from the oscillating and nonoscillating components of the laser ponderomotive force, is formed around the foil surfaces. This field combines radiation-pressure acceleration and target normal sheath acceleration to produce a single quasimonoenergetic ion bunch. A criterion for this mechanism to be operative is obtained and verified by two-dimensional particle-in-cell simulation. At a laser intensity of ∼5.5×10(22)  W/cm(2), quasimonoenergetic GeV proton bunches are obtained with ∼100  MeV energy spread, less than 4° spatial divergence, and ∼50% energy conversion efficiency from the laser.
authors.affiliation: Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan.
authors.forename: H B
authors.initials: HB
authors.lastname: Zhuo
authors.forename: Z L
authors.initials: ZL
authors.lastname: Chen
authors.forename: W
authors.initials: W
authors.lastname: Yu
authors.forename: Z M
authors.initials: ZM
authors.lastname: Sheng
authors.forename: M Y
authors.initials: MY
authors.lastname: Yu
authors.forename: Z
authors.initials: Z
authors.lastname: Jin
authors.forename: R
authors.initials: R
authors.lastname: Kodama