In this speech, our recent study on high-power Yb-doped fiber lasers operating near 980 nm will be reported. Our study is mainly focused on the 980-nm fiber lasers fabricated with the step-index double-cladding Yb-doped fiber. The background and motivation of our study will be firstly introduced. Then, our study on the high-brightness high-power 980-nm fiber lasers will be given, where the study on the 150-W-level 980-nm Yb-doped fiber laser with M² factor smaller than 2 will be presented. After that, our study on the high-efficiency high-power 980-nm fiber lasers will be introduced, where the study on the 1.5-kW 980-nm Yb-doped fiber laser will be presented. The factor limiting the power scalability of Yb-doped fiber amplifier operating near 980 nm will also be discussed in brief at the end of this speech.

Jianqiu Cao received the graduate degree in Applied Physics from Dalian University of Technology, China, in 2003, and his M.S. and Ph.D. in Optical Engineering from National University of Defense Technology, China, in 2005 and 2010, respectively. He joined the College of Optoelectronic Science and Engineering, National University of Defense Technology, in 2010 as a Lecturer and was promoted to an Associated Professor in 2016. Now, he is a Researcher in Optical Engineering in the College of Advanced Interdisciplinary Studies, National University of Defense Technology. His current research interests include high-power fiber lasers, nonlinear fiber optics, and advanced fiber design. This led to developments of super fluorescent fiber sources operating near 980 nm and 1060 nm, high-power Yb-doped fiber lasers operating near 980 nm, distributed side-coupled cladding-pumped fiber lasers, and thermal and nonlinear effect analysis in fiber lasers. He has co-authored more-than 100 publications in scientific journals and conference proceedings and holds 6 patents.