| Autor: |
Daniil Kartashov, Skirmantas Ališauskas, Audrius Pugžlys, Mikhail N Shneider, Andrius Baltuška |
| Předmět: |
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| Zdroj: |
Journal of Physics B: Atomic, Molecular & Optical Physics; 5/14/2015, Vol. 48 Issue 9, p1-1, 1p |
| Abstrakt: |
We present the theoretical model for a single-pass, discharge-type standoff nitrogen laser initiated by a femtosecond filament in nitrogen gas. The model is based on the numerical solution of the kinetic equation for the electron energy distribution function self-consistently with balance equations for nitrogen species and laser equations. We identify the kinetic mechanisms responsible for a buildup of population inversion in the filament afterglow plasma and determine the dependence of population inversion density and the parameters of nitrogen lasing at a 337 nm wavelength corresponding to the transition between the C3Πu (v = 0) excited and the X1Σg (v = 0) ground electronic states in a nitrogen molecule on the polarization and wavelength of the driver laser pulse used to produce the filament. We show that population inversion is achieved on an ultrafast time scale of ≈10 ps and decays within the time: <100 ps. We derive the low-signal gain 2.2 cm−1 for lasing from a circularly polarized 0.8 μm near-IR filament and 0.16 cm−1 for a linearly polarized 4 μm mid-IR filament. The results of the numerical simulations demonstrate good quantitative agreement with the experimental measurements. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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