Prospects for development of cw gas-discharge collision lasers based on self-terminating atomic transitions

An analysis was made of the feasibility of maintaining a steady or quasisteady population inversion of the resonant and metastable levels of a metal atom as a result of collisional depopulation of the metastable level by heavy particles in the course of a gas-discharge excitation of an active medium. The criteria for distinguishing self-terminating and quasi-cw lasing of pulsed metal vapor lasers are formulated. It is found that the parameters of a high-pressure discharge needed to ensure collisional lasing cannot be attained under realistic conditions. Numerical calculations for a low-pressure discharge show that collisional depopulation of metastable levels of metal atoms is frequency incapable of ensuring maintenance of a constant population inversion.