Splash plasma channels produced by picosecond laser pulses in argon gas for laser wakefield acceleration

水田 好雄*; 細貝 知直*; 益田 伸一*; Zhidkov, A.*; 牧戸 啓悟*; 中新 信彦*; 梶野 祥平*; 西田 明憲*; 神門 正城; 森 道昭; et al.

Physical Review Special Topics; Accelerators and Beams, 15(12), p.121301_1 - 121301_10, 2012/12

https://doi.org/10.1103/PhysRevSTAB.15.121301

Laser wakefield acceleration is capable of generating electron bunches with high quality: quasi-monoenergetic, low in emittance, and a very short duration of the order of ten femto-seconds. Such femtosecond bunches can be used to measure ultrafast phenomena. We conducted experiments for controllable electron bunch generation. Short-lived, 10 ps, deep plasma channels, with their lengths of 1 mm and diameters of 20 m, are observed and characterized in Ar gas jets irradiated by moderate intensity, 10 W/cm, laser pulses with a duration from subpicosecond to several picoseconds. The channels, upon 2D particle-in-cell simulations including ionization, fit well in the guiding of high intensity femtosecond laser pulses and, therefore, in laser wakefield acceleration with a controllable electron self-injection.