Collision gas-discharge laser utilizing europium vapor. II. Inversion population mechanism

An analysis was made of the excitation mechanisms of the ^7,9P upper levels of the europium ion and of the relaxation of the lower ⁷D⁰ levels. It was found that the upper laser states of the ⁹P type were excited by collisions of europium atoms in the ground state with electrons. The ⁷P levels were excited by collisions of europium ions with helium atoms. The lower levels were deactivated by collisions of europium ions with helium atoms. The factors limiting the output power were considered. A specific output power of 3 W/cm³ was obtained for a tube of 0.7-cm diameter operating under quasicontinuous conditions with an efficiency of 0.6%.