Evidence of Resonant Surface-Wave Excitation in the Relativistic Regime through Measurements of Proton Acceleration from Grating Targets

T Ceccotti (1) , V Floquet (1) , A Sgattoni (2) , A Bigongiari (3) , O Klimo (4) , M Raynaud (3) , C Riconda (5) , A Heron (6) , F Baffigi (2) , L Labate (2) , L. A. Gizzi (7) , L Vassura (5) , J Fuchs (8) , M Passoni (2) , M Květon (4) , F Novotny (4) , M Possolt (4) , J Prokůpek (9) , J Proška (4) , J Pšikal (4) , L. Stolcova (9) , A Velyhan (9) , M Bougeard (10) , P D 'Oliveira (10) , O Tcherbakoff (10) , F Réau (10) , P Martin (10) , A Macchi (2)

1 PHI - Physique à Haute Intensité
2 INO - Istituto Nazionale di Ottica
3 LSI - Laboratoire des Solides Irradiés - Irradiated Solids Laboratory
4 FJFI CTU - Faculty of Nuclear Sciences and Physical Engineering [Prague]
5 LULI - Laboratoire pour l'utilisation des lasers intenses
6 CPHT - Centre de Physique Théorique [Palaiseau]
7 Intense Laser Irradiation Laboratory–IPCF
8 LPS - Laboratoire de Physique des Solides
9 Institute of Physics [Prague]
10 LIDYL - Laboratoire Interactions, Dynamiques et Lasers (ex SPAM)

The interaction of laser pulses with thin grating targets, having a periodic groove at the irradiated surface, is experimentally investigated. Ultrahigh contrast ($ 10 12) pulses allow us to demonstrate an enhanced laser-target coupling for the first time in the relativistic regime of ultrahigh intensity >10 19 W=cm 2. A maximum increase by a factor of 2.5 of the cutoff energy of protons produced by target normal sheath acceleration is observed with respect to plane targets, around the incidence angle expected for the resonant excitation of surface waves. A significant enhancement is also observed for small angles of incidence, out of resonance.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

T Ceccotti, V Floquet, A Sgattoni, A Bigongiari, O Klimo, et al.. Evidence of Resonant Surface-Wave Excitation in the Relativistic Regime through Measurements of Proton Acceleration from Grating Targets. Physical Review Letters, 2013, ⟨10.1103/PhysRevLett.111.185001⟩. ⟨hal-01329909⟩