Radiation-Resistant Germanosilicate Multimode Fiber Light Guides

The effect of gamma-irradiation on optical losses at a wavelength of 1.31 to 1.55 mu m in multimode quartz fibers with a core doped with 20 mol % GeO2 is considered. Germanium oxygen-deficient centers in the core material are the main reason for the low radiation resistance of such optical fibers. The elimination of these defects in the MCVD preform technology reduces the radiation-induced attenuation in germanosilicate light guides to a level close to that of light guides with a pure quartz glass core. The increase in optical losses induced by radiation in the studied fibers is largely due to the contribution of Rayleigh scattering.