Influence of the pumping regime on lasing of an He–Xe optical-breakdown plasma

An experimental investigation was made of lasing of an optical-breakdown plasma in an He–Xe gas mixture exposed to CO₂ laser radiation. A wide range of pump pulse energies and durations and active mixture pressures was used. Lasing was realized on four Xe I transitions (λ = 2.03, 2.65,3.4, and 3.65μ). The pump pulse duration was found to exert a strong influence on the lasing characteristics of the optical breakdown plasma. An analysis was made of the role of gasdynamic processes in the interaction of the CO₂ laser radiation with the gas close to a target during the buildup of inversion. A quasi-cw lasing regime of the recombination laser in the optical breakdown plasma was observed.