An optically pumped carbon monoxide laser operating at elevated temperatures

A flowing gas, optically pumped, CO laser has been designed and built. The laser has been made to operate on the fundamental (≈5 μm) infrared bands of the CO vibrational states. The laser is powered by absorption of continuous wave radiation from an electric-discharge-excited CO laser. With this system, the kinetics of the establishment and maintenance of strong population inversions in CO at temperatures above 300 K is studied, independently of the complications of the electron impact processes and of other chemical channels which are present in electric discharge CO lasers. Lasing is obtained at temperatures up to 450 K, well above the cryogenic operating temperatures of conventional electric discharge CO lasers. The vibrational population distribution in the optically pumped laser is measured and the laser output power is determined as a function of the system operating parameters. Laser power conversion factors up to 14% have been observed. An optically pumped CO laser kinetic model is used to analyze the experimental results, providing insight into the details of secondary lasing kinetics. (paper)