High-power supersonic CO laser on fundamental and overtone transitions

Lasing parameters of a rf discharge-pumped CO laser in a subsonic gas flow with subsequent cooling of the laser medium in a supersonic flow are studied. The output power of the laser achieved 2.1 kW for the efficiency up to 21% in the spectral range 4.9—5.7 μm corresponding to the V+1→V fundamental vibrational transitions in the CO molecule. The laser output power at the V+2→V first vibrational overtone transitions (2.6—2.7 μm) was 50 W. Possible ways of improving the laser design for generating radiation at higher overtone transitions of the CO molecule are discussed.