Effect of SF6 and NF3 additives on UV and IR lasing in nitrogen

Abstract

The lasing regimes of nitrogen laser on the C3Πu — B3Πg transition with a high-energy long laser pulse under pumping by a transverse discharge in N2 — SF6 (NF3) mixtures from generators with a semiconductor opening switch is studied. Laser pulses with two peaks and controlled delay between these peaks are obtained. It is shown that the time interval between the peaks may exceed 50 ns for N2 — NF3 mixtures. The conditions for obtaining effective UV lasing with a laser pulse width of more than 50 ns at the base level are determined. A possibility of depopulating the lower level of the C3Πu — B3Πg transition by induced transitions in the first positive B3Πg — A3Σu+ system is shown; this process makes it possible to expand the pulse to 100 ns at λ = 337.1 nm. The highest lasing energy and power in the IR and UV spectral ranges are obtained for nitrogen lasers with spark preionisation.