The population inversion in ion alkaline-earth metal vapor lasers, using the pumping by charge transfer in pulsed hollow cathode discharge.
The results of the study of the Be+, Ca+ and Sr+ level population, and laser gain dependences on the variation of pulsed hollow cathode discharge (HCD) parameters for Be-He, Ca-Ar, Ca-Kr, and Sr-Kr mixtures are presented and discussed. Pumping of excited metal ion levels and the population inversion creation goes through the thermal energy charge-transfer reaction between ground state buffer rare gas ions and neutral metal atoms. Owing to the specific energy distribution of electrons in HCD, the second-kind collisions of excited metal ions with HCD plasma thermal electrons take place, which redistribute metal ion population and influence laser parameters. The results of detailed studies of the our kinetic model of pulsed HCD plasma in Kr-Sr vapor mixture show that for 62Р-62S and 62Р-52D Sr+ laser transitions the decreasing of 62Р Sr+ upper laser level population and increasing the population of 52D levels which closely spaced with 62Р levels take place. The numerical calculations were made for the pulse HCD, and their results predict the population inversion and laser action for 32 new Be+, Ca+ and Sr+ laser transitions in visible and infrared ranges.