10.6084/M9.FIGSHARE.C.6240999.V1
Qi Lu
Qi
Lu
Xiang Zhang
Xiang
Zhang
Santiago Lopez
Santiago
Lopez
Haicheng Mei
Haicheng
Mei
Liang Xu
Liang
Xu
Qingqing Liang
Qingqing
Liang
Aurelien Houard
Aurelien
Houard
Vladimir Tikhonchuk
Vladimir
Tikhonchuk
Andre Mysyrowicz
Andre
Mysyrowicz
Eduardo Oliva
Eduardo
Oliva
Spectral splitting of the lasing emission of nitrogen ions pumped by 800 nm femtosecond laser pulses
We report on a spectral splitting effect of the cavity-less lasing emission of nitrogen ions at 391.4 nm pumped by the 800 nm femtosecond laser pulses. It was found that with the increase of the nitrogen gas pressure and pump pulse energy, both R and P branches experience spectral splitting. With an external injected seeding pulse, similar split spectral line is observed for the amplified emission. In contrast, for the fluorescence radiation, no such spectral splitting phenomenon is observed with much more abundant R branch structures. Our theoretical model considers gas ionization by the pump pulse, the competition of excitation of all relevant electronic and vibrational states and an amplification of the seeding pulse in the plasma with a population inversion. The model reproduces this spectral splitting effect, which is attributed to the gain saturation resulting in the oscillation of the amplitude of the amplified signal.
Uncategorized
Optica Publishing Group
2023
2023-01-24
2023-01-24
Collection
10.6084/m9.figshare.c.6240999
CC BY 4.0