Highly-efficient ion acceleration in laser plasma via interaction of intense laser pulse with cluster-gas target

Fukuda, Yuji; Tampo, Motonobu; Kando, Masaki; Hayashi, Yukio; Kawase, Keigo*; Faenov, A. Ya.*; Pikuz, T. A.*; Nakamura, Tatsufumi; Sakaki, Hironao; Pirozhkov, A. S.; Shimomura, Takuya; Kiriyama, Hiromitsu; Kanasaki, Masato; Yamauchi, Tomoya*; Kodama, Ryosuke*; Kondo, Kiminori; Bulanov, S. V.

We present substantial enhancement of accelerated ion energies up to 10-20 MeV per nucleon by utilizing the unique properties of the cluster-gas target irradiated with 40-fs laser pulse of only 150 mJ energy, corresponding to approximately tenfold increase in ion energies compared to previous experiments using thin foil targets. A particle-in-cell (PIC) simulation infers that the high energy ions are generated at the rear side of the target due to the formation of a strong dipole vortex structure in sub-critical density plasmas. The latest experimental results of ion acceleration using the cluster-gas target with 40-fs laser pulses of 1-J energy will be also presented in the presentation.