中文摘要：

<正> Propagation of intense femtosecond laser pulses (60 fs,800 nm,120 mJ,6 × 1017W/cm2 in vacuum)in supersonic （CD4）N and （D2）N cluster jets at different backingpressures was studied.Pump-probe interferometry is employed to investigate the propagation oflaser beams in dense cluster jets by examining the electron density distribution of plasma channels.It was found that propagation effects,including ionization-induced defocusing and laserattenuation of incident pulses,are very different in the （CD4）N and （D2）N cluster jets.Differentionization states of CD4 and D2 molecules were observed by analyzing the transverse electron densityprofiles of the plasma channels and should be considered as a major reason for the differencesin the propagation effects.Numerical simulations of the nonlinear propagation of femtosecondlaser pulses in （CD4）n and （D2）N cluster jets were performed,and the results indicated a goodreproduction of the experimental data.

英文摘要：

Propagation of intense femtosecond laser pulses （60 fs, 800 nm, 120 m J, 6 × 10^17 W/cm^2 in vacuum） in supersonic （CD4）N and （D2）N cluster jets at different backing pressures was studied. Pump-probe interferometry is employed to investigate the propagation of laser beams in dense cluster jets by examining the electron density distribution of plasma chan- nels. It was found that propagation effects, including ionization-induced defocusing and laser attenuation of incident pulses, are very different in the （CD4）N and （D2）N cluster jets. Different ionization states of CD4 and D2 molecules were observed by analyzing the transverse electron density profiles of the plasma channels and should be considered as a major reason for the differences in the propagation effects. Numerical simulations of the nonlinear propagation of femtosecond laser pulses in （CD4）N and （D2）N cluster jets were performed, and the results indicated a good reproduction of the experimental data.