Influence of the pump pulse repetition frequency on the power deposited in a copper vapor laser discharge

Investigations carried out on a coaxial copper vapor laser showed that, on varying the excitation frequency from 0.5 to 6.0 kHz, the energy deposited in the discharge increased from 10 to 70% of the storage capacitor energy. There were two serious limitations to increasing the pump power, imposed by constriction of the discharge and by the generation of heat in the active medium. It was shown that the use of a coaxial geometry for the active zone in copper vapor lasers, with both longitudinal and transverse discharges, made it possible to increase the ultimate pump power substantially without changing the average temperature of the gas in the active zone and so to increase the ultimate lasing pulse repetition frequency. Estimates showed that the ultimate pump power, for a ratio of the wall radii of the coaxial active medium of ~ 1.3, can exceed by an order of magnitude the ultimate pump power for a tube.