Theoretical analysis of fluorescence signals in filamentation of femtosecond laser pulses in nitrogen molecular gas
نویسندگان
چکیده
We study numerically and analytically the role of the combined effect of self-focusing, geometrical focusing, and the plasma defocusing in the formation of the fluorescence signal during the filamentation of a Ti:sapphire laser pulse in nitrogen molecular gas. Results of numerical simulations are used to estimate the number of excited ions in the focal volume, which is proportional to the fluorescence signal. We find good agreement between the theoretical results and the experimental data, showing that such data can be used to get further insight into the effective focal volume during filamentation of femtosecond laser pulses in transparent media.
منابع مشابه
Space-based Femtosecond Laser Filamentation
Contents 1 INTRODUCTION 2 2 Model for numerical simulations of filamentation from orbit 5 2. 5 Conclusions 23 6 Next steps 24 A Full theoretical model of vertical propagation of ultrashort laser pulses 25 A.
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