Influence of Pre-Radiation and Photo-Bleaching on the Yb-Doped Fiber Laser Radiated with Gamma-ray

To improve the radiation resistance of Yb-doped fiber lasers, we investigate the influence of pre-radiation and photo-bleaching on the gamma-radiated laser's performance. When the gamma radiation dose is within 10 krad(Si) with a radiation dose rate less than 0.4 rad(Si)/s, compared to the output power of a non-pre-radiated Yb-doped fiber laser, the pre-radiation technique could enhance the radiation resistance against gamma-ray. However, the mode instability threshold was decreased, which was caused by the cumulated radiation-induced attenuation of pre-radiation and radiation. Based on an electronic probe micro-analyzer, the Yb-doped active fiber was Yb-doped aluminophosphosilicate ternary fiber; therefore, the radiated defects were mainly hole-related defects. A laser diode centered at 532 nm was chosen as the photo-bleaching laser source, which could recover 45.2% of the radiated-induced attenuation and increase the mode instability threshold. This work demonstrates the influence of pre-radiation and photo-bleaching on the radiation resistance against the gamma-ray of Yb-doped fiber lasers, which are of significance in the design and fabrication of related fiber lasers.