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

Opt Lett. 2020 Sep 15;45(18):5173-5176. doi: 10.1364/OL.398869.

Abstract

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 Er3+ 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 underγ-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.