Gas lasers utilizing cascade transitions in linear triatomic molecules

Abstract

Some characteristics of gas lasers utilizing cascade transitions in linear triatomic molecules are discussed. General operating conditions are determined for a pulsed cascade laser with an arbitrary method of excitation and a simple technique is described for the calculation of its maximum energy output. This approach is used to analyze some features and to give an estimate of the energy yield of three-frequency CO2 lasers with thermal and electric pumping. Practical recommendations on the development of cascade lasers are given and specific methods of improving their efficiency are proposed. It is found that under typical conditions the average radiation power at the ~16 µ wavelength in cascade CO2 lasers can reach 0.5–0.6 W/cm3 in gasdynamic lasers and ~4.5 W/cm3 in an electric-discharge laser with a supersonic gas flow rate.