Radiation-resistant flatness-shaped spectrum erbium-doped photonic crystal fiber source employing multiple self-compensating methods.

A novel scheme of radiation-resistant flatness-shaped spectrum erbium-doped photonic crystal fiber source (EDPCFS) employing multiple self-compensating methods is proposed. We first develop a sort of radiation-resistant highly erbium-doped photonic crystal fiber (EDPCF) with the cutoff wavelength of 520 nm, which ensures that the pump light and most energy of the green light from upconversion of could participate in photo-annealing to reduce the radiation-induced background attenuation (RIBA) of the EDPCFS under radiation environment. To minimize the spectrum variation from radiation-induced active band attenuation (RIABA), the original spectrum is optimized employing an improved double pumped backward (DPB) configuration. With a gain flattening filter and closed-loop feedback control technology, a radiation-resistant EDPCFS with a linewidth larger than 41 nm is achieved, and it experimentally demonstrates a significantly improved mean-wavelength stability of 0.42 ppm/krad with the output power attenuation of 0.09 dB under-irradiation of 200 krad. The novel radiation-resistant EDPCFS proposed is quite feasible for strategic interferometric fiber-optic gyroscopes (IFOGs) working in high-dose radiation environment.