ENHANCED GAIN AND OUTPUT POWER OF A SEALED-OFF RF-EXCITED CO2 WAVE-GUIDE LASER WITH GOLD-PLATED ELECTRODES

The small-signal gain and the laser output power have been measured in a cw sealed-off rf-excited CO2 waveguide laser for two different elec trode materials, gold-plated copper and aluminum, at several excitatio n frequencies, gas pressures and mixture compositions. In the case of the gold-plated electrodes an enhancement of the gain up to a factor o f 2 and the output power up to a factor of 1.4 with time at a frequenc y of 190 MHz and 60 Torr of 1:1:5+5% (CO2:N-2:He+Xe) mixture is observ ed. This is believed to be the result of the gold catalytic activities which are favored by increased electrode temperatures and helium rich gas compositions.