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

The lasing regimes of nitrogen laser on the C³P_u — B³P_g 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 C³P_u — B³P_g transition by induced transitions in the first positive B³P_g — A³Σ_u⁺ 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.