Measurements of intrinsic efficiency and parameters of an electronbeam pumped ArXe laser

Measurements of the output energy and intrinsic efficiency of an electron-beam-pumped ArXe laser operating on the 1.73-μm line are reported. A 220-kV electron beam was used to pump either an 11×11×50 cm³ or an 11×11×25 cm³ active volume. Small-signal gain, nonsaturable loss, and saturation flux were deduced from a Rigrod analysis of the output energies as a function of output coupler reflectivity. Electron beam pump powers ranging from 2.2 to 16.2 kW/cm³ were employed. At a pump power of 2.2 kW/cm³ a small signal of 0.035 cm^-1 , a gain-to-loss ratio of 272, and a saturation flux of 2.1 kW/cm ² were determined. Intrinsic efficiencies of 4% were obtained at the lower pump powers. From the measurements of the laser output it is clear that the secondary electrons have a significant impact on the laser kinetics and efficiency