A Self-Consistent Model for Negative Glow Discharge Lasers: The Hollow Cathode Helium Mercury Laser

A model for negative glow metal-vapor ion lasers that self-consistently describes the dynamics of the negative glow and the cathode sheath regions of the discharge has been developed. The model computes the electron energy distribution and the population of relevant excited states in the negative glow self-consistently with the charged particle fluxes and electric field distribution in the cathode sheath. Its application to the study of the helium-mercury charge transfer ion laser is reported. The model accurately depicts the operation of a hollow cathode in the laboratory, where for a defined cathode geometry and material, the discharge characteristics are determined by the selected discharge voltage and the gas pressure. The laser output power calculated as a function of the discharge parameters is in good agreement with experimental measurements reported in the literature. The model can be modified to simulate other negative glow discharge lasers, such as electron-beam pumped CW ion lasers.