THEORY OF A CW SUPERSONIC NITROGEN RECOMBINATION LASER

Abstract
Quasi-two dimensional model calculations show the possibility to realize a cw atomic nitrogen laser, pumped by the recombination process in rapidly expanded plasma flows. Sufficient gain for lasing is demonstrated for stagnation conditions of 13 000 ≤ T_o ≤ 24 000 K and 2 ≤ P_o ≤ 30 kPa. Location and size of the gain regimes in the flow direction depend on the plasma starting condition. At a wavelength of 0.91 µm values of small signal gain up to 0.6 m^-1 can be attained. The model is described and some selected results are presented. The effect of the electron heat conduction is discussed.