Stimulated emission at 18.4 μ from a gasdynamic CO2 laser with electric-arc heating

A CO₂–Ar gasdynamic laser (λ = 18.4 μ) with pulsed electric-arc heating was constructed and investigated. Measurements of the emission wavelength (18.38±0.04 μ) indicated that lasing occurred in the Q branch of the 03¹0–10⁰0 transition. The maximum energy per ~20 msec pulse was ~0.04 J when the initial temperature and pressure in the forechamber were T₀ = 1000 °K and p₀ = 10 atm for a mixture of the CO:Ar = 1:2 composition. The energy per pulse decreased smoothly when the CO₂ concentration was varied, which was in agreement with calculations. Estimates of the power density inside the resonator gave ~3 kW/cm² and the specific energy yield from the gas flow was ~10 J/g.