Investigation of the effects of hydrogen and deuterium on copper vapour laser performance

We report a detailed study of the effects on copper vapour laser performance of the addition of small partial pressures of gaseous hydrogen, deuterium and other trace gases to the neon buffer gas. Increases in output power by typically 30% are observed for a small-scale (6 W) device and the spatial characteristics of the output beam are significantly altered. Increased power deposition due to improved impedance matching is shown to be a minor effect. Instead, the changes to output power and the voltage/current characteristics during the excitation pulse and the interpulse period are attributed primarily to enhanced plasma cooling by elastic interactions resulting in reduced prepulse electron densities.