Stimulated emission mechanisms of a λ = 585.3 nm gas-discharge neon–hydrogen laser

An investigation was made of the mechanisms of pulsed lasing due to the 585.3 nm NeI transition in an Ne–H₂ mixture in hollow-cathode and longitudinal discharges. It was established that lasing in the afterglow of both types of discharge was due to pumping of the upper active level mainly by three-body recombination of neon ions, whereas lasing during a current pulse in a hollow-cathode discharge was due to electron impact pumping. It was found that, in a longitudinal discharge at high currents, a recombination nonequilibrium state could form even during passage of the current and then lasing during a current pulse was due to recombination pumping. It was established that the depopulation of the lower active level as a result of the Penning reaction with hydrogen was selective. It was found that elastic collisions with electrons had a strong influence on the temporal characteristics of the lasing in a recombining plasma.