Radiation damage of optical fiber waveguides at long wavelengths.

Measurements of the radiation-induced optical attenuation at 1.3 microm and the induced absorption spectra (0.4-1.7 microm) of state-of-the-art pure synthetic silica and doped silica core optical fiber waveguides have been undertaken to characterize their radiation response at long wavelengths. It has been observed that radiation-induced absorption bands at long wavelengths can give rise to substantial induced losses at both 1.3 and 1.55 microm in some fibers, especially those doped with P or B; the ratio of the damage at 1.3 and 1.55 microm to that at 0.82 microm in these fibers has been found to be only ~0.29 and 0.71, respectively. In contrast, pure fused silica and binary Ge-doped silica core fibers have shown the greatest hardness at long wavelengths. Suggestions have been made for the optimum wavelengths and preferred fiber compositions to minimize the effects of nuclear radiation in fiber-optic communications systems operating at long wavelengths.