Radiation Effects in Doped-Silica Optical Waveguides

A study was made of the losses induced in dopedsilica optical waveguides from nuclear radiation. Several experiments were performed. The effects of temperature on the losses induced from in-situ 60Co irradiation were measured. The radiation sensitivity of Ge-doped silica fibers was found to increase at low temperatures. This increase was not observed in fibers containing phosphorus. Short pulse flash x-ray irradiations showed that the temperature dependence of the transient losses was suppressed in phosphorus doped fibers. Neutron irradiation with a fission product spectrum produced damage which corresponded to the neutron ionizing dose. Data is presented on the 60Co losses as a function of dose rate. The 60Co losses are discussed in terms of the temperature dependence of the transient losses for different fiber compositions.