Optical Properties and Laser Output of Heavily Yb-Doped Fiber Prepared by Sol-Gel Method and DC-RTA Technique

Heavily Yb-doped (14300 ppm) preforms and fibers were prepared by the sol-gel method and dip coating-rapid thermal annealing technique. Optical properties of these preforms and fibers were measured and discussed. A fiber laser at a 1053-nm wavelength was realized and its slope efficiency was measured to be 88.4%. The excellent performance of the fiber laser and repeatability show that the novel approach described in this paper is capable of providing low-cost high-level rare earth-doped fibers for amplifiers and fiber lasers.