Influence of the gas mixture composition and cathode material on the output power of a copper vapor laser

The highest output powers and lasing efficiencies for self-heated active elements in copper vapor lasers, containing electrodes mounted in the high-temperature zone and employing a longitudinal discharge, were achieved using neon as the buffer gas and refractory metals as the cathode material. In this case the discharge on the cathode surface was localized in a spot of about 1 mm diameter, the cathode material had no influence on the discharge and lasing characteristics, and the lowering of the laser output power on increase in the neon pressure to 50-80 kPa was relatively slight. The addition of impurity gases with ionization potentials below that of neon reduced markedly the efficiency of the laser cycle.