High-pressure N+2 laser emitting violet radiation

Stimulated emission at the λ = 427.8 nm wavelength was obtained as a result of excitation of He + 0.02 – 0.2 % N₂ mixtures by an electron beam ( W ≈ 200 keV, I ≈ 3kA, j ≈ 50 A/cm², τ ≈50 nsec). The upper laser level N⁺₂(B²∑⁺_u) was populated by the transfer of energy from molecular helium ions. The observed stimulated violet radiation was due to the first negative band of the nitrogen ion (B²∑⁺_uυ'=0→X²∑⁺_gυ''=1). The energy characteristics of the laser were determined as a function of the composition of the mixtures at pressures of 0–7 atm.