Radiation-Resistant Er-Doped Fiber Based on Ge-Ce Co-Doping

We investigated the radiation responses of Ge-Ce co-doped erbium-doped fibers (EDFs) under gamma radiation with a dose up to 1000 Gy and a dose rate of 0.2 Gy/s. Three EDFs with low or high concentrations of Ge or Ce were fabricated by modified chemical vapor deposition (MCVD). The absorption spectra and amplification performance of the three Ge-Ce co-doped EDFs before and after radiation were tested and analyzed in detail. The radiation-induced absorption (RIA) can be dramatically weakened by heavily co-doping Ge and Ce, and 0.8 dB radiation-induced gain degradation at 1550 nm was obtained in the erbium-doped fiber amplifier (EDFA) with heavy Ge and Ce doping at a dose of 1000 Gy. Furthermore, the possible mechanism of Ce and Ge effects on radiation tolerance enhancement is discussed. Relevant results indicate that the Ge-Ce co-doped EDF has significant performance improvements in radiation resistance, making it ideal for applications in harsh radiation environments.