Control of the Spectral Composition of Coherent Radiation on Molecular Nitrogen Ions in Laser Plasma Using Two-Color Pumping

Abstract

In recent years, laser sources created in airborne laser plasma by powerful femtosecond radiation pulses have been rapidly developing. This work studies coherent radiation generation on \({\text{N}}_{2}^{ + }\) ions in laser plasma using two-color pumping at λ = 950 and 475 nm. It is shown that the addition of second harmonic radiation, wavelength of which is closer to the lasing lines on \({\text{N}}_{2}^{ + }\) ions compared to the first harmonic, increases the intensity and stability of supercontinuum radiation which acts as seed radiation for the lasing. Such pumping allows lasing on new lines and controlling the intensity and spectral composition of the generated radiation. The results can be useful for establishing the way(s) of creating population inversion in laser plasma on molecular nitrogen ions.