Gain measurements on the sequence bands in a TEA-CO2 amplifier

Abstract

Small‐signal gains as high as 1.5% cm⁻¹ have been measured in a TEA‐CO₂ amplifier on the 00°2‐ (10⁰1, 02⁰1)_I,II sequence bands. The ratio of the gain coefficient of the sequence bands over the gain coefficient of the regular bands has been observed to be independent of either the CO₂ or He proportion in the gas mixture. It has also been found to increase with the electrical energy dumped into the active medium and to reach a value of 1/3 at an excitation density of 140 J/l. Gain on the sequence bands has been found to be responsible for the anomalously high gain coefficient that is measured at low J values of the R branch of the regular 9.4‐μm transition in TEA amplifiers.