Er/Yb co-doped 345-W all-fiber laser at 1535 nm using hybrid fiber
Wenzhen Li, Qiang Qiu, Long Yu, Zhimu Gu, Le He, Shaokun Liu, Xiaoke Yin, Xinyue Zhao, Jinggang Peng, Haiqing Li, Yingbin Xing, Yingbo Chu, Nengli Dai, Jinyan Li
Abstract
The 1.5-µm fiber laser is widely used in the fields of laser lidar, remote sensing, and gas monitoring because of its advantages of being eye-safe and exhibiting low atmospheric transmission loss. However, due to the ∼1-µm amplified spontaneous emission (ASE) of the Er/Yb co-doped fiber (EYDF), it is difficult to improve the laser power. Here, we simulated the effect of the Er 3+ concentration and the seed power on ∼1-µm ASE, and fabricated a large mode area EYDF by the modified chemical vapor deposition process. Additionally, a piece of ytterbium-doped fiber was introduced into the master oscillator power amplifier (MOPA) configuration to absorb the generated ∼1-µm ASE simultaneously. Experimental results show that an output power of 345 W with a slope efficiency of 43% at 1535 nm is obtained in an all-fiber configuration, profiting from effective suppression of ∼ 1-µm ASE. To the best of our knowledge, this is the highest output power available with an Er/Yb co-doped fiber from an all-fiber MOPA configuration.