Yb 3+ heavily doped photonic crystal fiber lasers prepared by the glass phase-separation technology

• Published in: Optics express 2017-10, Vol.25 (20), p.24061
• Main Authors: Chu, Yingbo, Yang, Yu, Hu, Xiongwei, Chen, Zhangru, Ma, Yunxiu, Liu, Yongguang, Wang, Yibo, Liao, Lei, Xing, Yinbin, Li, Haiqing, Peng, Jinggagn, Dai, Nengli, Li, Jinyan, Yang, Luyun
• Format: Article
• Language: English
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.25.024061

We report a Yb heavily doped photonic crystal fiber with 30 μm core diameter manufactured for the first time by an alternative technique. Silica core rods with a diameter of 3 mm and a length of 280 mm were prepared by the sodium-borosilicate glass phase-separation technology. The measurements show that the fiber has an Yb concentration of 22810 ppm by weight, and a resultant absorption of approximately 8.5 dB/m at 976 nm. The Yb ions are distributed throughout the fiber core with an excellent homogeneity. The laser performance demonstrates a high slope efficiency of 64.5% for laser emission at 1033.4 nm and a low power threshold of 3 W within a short fiber length of 1 m. This novel approach provides an alternative means of preparing large active silica rods with high doping levels and excellent material homogeneity for large mode area fibers with complex designs.