Interaction between tW-Laser Pulses and Dense Gas-jet Targets

摘要

Experiments on producing high-energy electrons by intense laser pulses (7 x 10~17 W/cm~2) were curried out at moderately high-density plasmas (n_e_c approx approx 0.17) by using ultra-short laser pulses (100 fs). The transition of laser pulse propagation from smooth channeling to the complex filamentation was observed. The measured time to the transition of the propagation was P~-0.4P_gas~-0.8. The electron energy of above 1 MeV was observed. The dependence of the maximum electron energy on the laser power of P~(0.7-1.4) and on the gas density of P_gas~1.8-2.3) suggests that electrons gain energy by the stochastic heating.