Helong Li

TL;DR: In this article, the authors demonstrate the generation of narrowbandwidth emissions with excellent coherent properties at 391 and 428nm from N + (B 2 6 + (v 0 = 0)! X 2 6+ g (v = 0,1)) inside a femtosecond filament in air by an orthogonally polarized two-color driver field (i.e., 800nm laser pulse and its second harmonic).

TL;DR: In this paper, the authors demonstrate the generation of strong narrowbandwidth emissions with excellent coherent properties at 391 and 428 nm from molecular ions of nitrogen inside a femtosecond filament in air by an orthogonally polarized two-color driver field.

TL;DR: It is concluded that a postionization multiple-state coupling, through which the population can be transferred from the X2Σ_{g}^{+} state of N_{2} to the first electronically excited A^{2}Π_{u} state, leads to the depletion of the population in the X 2ΣΣ g state, and consequently, to thepopulation inversion between the X^{2]Σ{g}+ state and the B 2΢

TL;DR: Clean fluorescence emissions from free radicals CH, CN, NH, OH, and C(2), as well as atomic C and H, are observed when a femtosecond filament is formed in the laminar ethanol/air flame on an alcohol burner.

TL;DR: By solving the time-dependent Schrödinger equation, the oscillations in the three different frequency ranges are reproduced and it is shown that the coherent population transfer among the three electronic states of N_{2}^{+} creates the population inversion between the B^{2}Σ_{u} and X-X-X states.