title: Electron Acceleration by Relativistic Surface Plasmons in Laser-Grating Interaction.
abstract: The generation of energetic electron bunches by the interaction of a short, ultraintense (I>10(19)  W/cm(2)) laser pulse with "grating" targets has been investigated in a regime of ultrahigh pulse-to-prepulse contrast (10(12)). For incidence angles close to the resonant condition for surface plasmon excitation, a strong electron emission was observed within a narrow cone along the target surface, with energy spectra peaking at 5-8 MeV and total charge of ∼100  pC. Both the energy and the number of emitted electrons were strongly enhanced with respect to simple flat targets. The experimental data are closely reproduced by three-dimensional particle-in-cell simulations, which provide evidence for the generation of relativistic surface plasmons and for their role in driving the acceleration process. Besides the possible applications of the scheme as a compact, ultrashort source of MeV electrons, these results are a step forward in the development of high-field plasmonics.
authors.affiliation: Enrico Fermi Department of Physics, University of Pisa, 56127 Pisa, Italy.|National Institute of Optics, National Research Council (CNR/INO), u.o.s Adriano Gozzini, 56124 Pisa, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Fedeli
authors.affiliation: National Institute of Optics, National Research Council (CNR/INO), u.o.s Adriano Gozzini, 56124 Pisa, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Sgattoni
authors.affiliation: Enrico Fermi Department of Physics, University of Pisa, 56127 Pisa, Italy.|National Institute of Optics, National Research Council (CNR/INO), u.o.s Adriano Gozzini, 56124 Pisa, Italy.|LIDYL, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France.|University of Paris Sud, Orsay 91405, France.
authors.forename: G
authors.initials: G
authors.lastname: Cantono
authors.affiliation: LIDYL, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France.
authors.forename: D
authors.initials: D
authors.lastname: Garzella
authors.affiliation: LIDYL, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France.
authors.forename: F
authors.initials: F
authors.lastname: Réau
authors.affiliation: Department of Energy, Politecnico di Milano, Milan 20156, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Prencipe
authors.affiliation: Department of Energy, Politecnico di Milano, Milan 20156, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Passoni
authors.affiliation: Laboratoire des Solides irradiés, Ecole Polytechnique, CNRS, CEA/DSM/IRAMIS, Université Paris-Saclay, 91128 Palaiseau Cedex, France.
authors.forename: M
authors.initials: M
authors.lastname: Raynaud
authors.affiliation: FNSPE, Czech Technical University, Prague 11519, Czech Republic.
authors.forename: M
authors.initials: M
authors.lastname: Květoň
authors.affiliation: FNSPE, Czech Technical University, Prague 11519, Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Proska
authors.affiliation: Enrico Fermi Department of Physics, University of Pisa, 56127 Pisa, Italy.|National Institute of Optics, National Research Council (CNR/INO), u.o.s Adriano Gozzini, 56124 Pisa, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Macchi
authors.affiliation: LIDYL, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France.
authors.forename: T
authors.initials: T
authors.lastname: Ceccotti