Effect of gamma irradiation on characteristics of Yb-doped fiber materials

Yb-doped fibers are the key materials in high power lasers, its application performance will significantly decrease after irradiation with high-energy rays. Therefore, it is necessary to conduct in-depth research on the performance changes of Yb-doped fiber materials under irradiation. A series of optical fiber preforms and optical fibers were prepared by modified chemical vapor deposition combined with rare-earth chelate-doping method. The high-power output performance of the optical fibers and the optical properties of preforms before and after irradiation were studied. The experimental results show that the high-power output of Yb-doped fiber significantly decreased after low-dose irradiation. It can be seen from the absorption spectra that the main reason is that after irradiation, the Al-related defect concentration in the Yb-doped fiber materials increases, and the absorption loss in the visible region increases. Ce ions doping can reduce the increase of Al-oxygen hole centers (Al-OHCs) color center defects caused by radiation, reduce the decrease of Yb ions fluorescence lifetime, and suppress the radiation darkening of Yb-doped fibers to a certain extent. (authors)