Electron-Beam Induced Absorption and Hardening in Fiber-Optic Waveguides to 1060 nm Laser Pulses

摘要

For Corning Glass Work (CGW) and Valtec Corporation (VC) fiber-optic waveguides (FOWs), we have determined the coupling efficiencies (output/input energy) before (R sub 1 ) and after (R sub 2 ) electron-beam irradiation, the output energy density, the induced attenuation or loss (L/sub I/) and its decrease as a function of time, and hardening as a function of number of Febetron shots (N/sub T/). The FOWs were electron-beam irradiated with 8.3 to 12.3 J/cm exp 2 for a 2.36 to 2.84 x 10 exp 6 R ( exp 60 Co equivalent) dose. The output laser energy density varied from 0.19 to 2.12 kJ/cm exp 2 which was about 50% of the input surface threshold damage level previously measured in similar FOWs. The values of R sub 1 , 40.1 to 67.0%, were less than those previously measured. The induced attenuation (L/sub I/) as a function of recovery time (after electron-beam irradiation) was linear on log-log plot for a short time (