The characteristics of the cw neutral argon ir laser are studied using a variety of techniques. The output power enhancement effects of helium and chlorine gases are measured, and the reasons for the enhancement are determined. The gain is measured for the 2.397-µm, 2.208-µm, 2.062-µm, and 1.792-µm laser lines, using an internal cavity-loss method and a single-pass amplifier method. In addition, the saturation intensity is measured, and competition effects are studied. It is concluded that helium aids excitation of the upper laser levels by producing a significant increase in the electron temperature. Chlorine is shown to aid de-excitation of the lower laser levels by partially depopulating the metastable argon 4s levels that lie just below them.
A. B. Dauger and O. M. Stafsudd, "Characteristics of the Continuous Wave Neutral Argon Laser," Appl. Opt. 10, 2690-2697 (1971)