Fig. 1. Absorption spectra and corresponding radiation-induced attenuation of pristine and irradiated radiation-resistant erbium-doped fiber. (a)Pump band; (b)signal band

Fig. 2. Gain test diagram and cross-section of C-band radiation-resistant erbium-doped fiber

Fig. 3. Variation of gain versus pumping power at 1550 nm before and after irradiation of radiation-resistant erbium-doped fiber