A SPARK CHANNEL PLASMA ELECTRODE FOR A CO2-LASER GAS-DISCHARGE

A plasma electrode potentially suitable for dc discharge pumped lasers has been developed based on the repetitive creation of a spark channel. The high-density plasma is a source of charge carriers for the dc discharge, thereby largely eliminating the cathode and anode falls. Potential reduction improves with increasing spark repetition frequency until about 9 k Hz, at which point the falls are virtually eliminated. Fortuitously, the most beneficial regime of plasma electrode operation also appears to coincide with the optimum E/N range for CO2 laser vibrational excitation.