Comparison of Germanium-Stainless Steel Electrode Configurations for Possible Utilization in Electric Discharge HF Lasers.
AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
Pagination or Media Count:
An HF laser cavity was designed and constructed in which four electrode combinations were tested. The electrodes consisted of two stainless steel Chang-profiled electrodes and two 50-omega cm germanium electrodes. The four possible electrode combinations for anode and cathode were tested. Breakdown, sustaining, and arcing voltages were recorded, for each combination, over a range of 25-200 pulses per second for the following gases with their respective pressure ranges helium, 50-90 Torr nitrogen, 5-30 sulfur-hexafluoride, 3-15 Torr. The use of germanium as a cathode material resulted in substantially greater suppression of arc formation than the use of stainless steel. Helium, which sustained arcs at 60 Torr and 100 pps with a stainless steel cathode-anode, was found to be arc-free at pressures up to 90 Torr with repetition rates as high as 200 pps using a germanium cathode. similarly, sulfur-hexafluoride, which sustained arcing at 3 Torr and 150 pps with stainless steel electrodes was found to be arc-free at pressures over 13 Torr when germanium was used as a cathode. The use of germanium as both anode and cathode resulted in the highest suppression of arc formation. Author
- Lasers and Masers