高功率光纤激光器反向泵浦信号合束器信号光传输效率提升技术研究  

Study on signal light transmission efficiency enhancement of backward pump-signal combiners in high-power fiber lasers

作　　者：方泽远 尹路 闫明鉴 韩志刚 沈华 朱日宏 Fang Zeyuan;Yin Lu;Yan Mingjian;Han Zhigang;Shen Hua;Zhu Rihong(Shanghai Electro-Mechanical Engineering Institute,Shanghai 201109,China;MIIT Key Laboratory of Advanced Solid Laser,Nanjing University of Science and Technology,Nanjing 210094,China;School of Electronic Engineering and Optoelectronic Technology,Nanjing University of Science and Technology,Nanjing 210094,China)

机构地区：[1]上海机电工程研究所,上海201109 [2]南京理工大学先进固体激光工信部重点实验室,江苏南京210094 [3]南京理工大学电子工程与光电技术学院,江苏南京210094

出　　处：《红外与激光工程》2020年第10期110-119,共10页Infrared and Laser Engineering

基　　金：国家自然科学基金(61875087)。

摘　　要：在高功率光纤激光器反向泵浦信号合束器的制作过程中,经熔融拉锥后输出端的信号光纤纤芯变细,在与输入端信号光纤熔接时产生模场失配问题,造成反向泵浦信号合束器的信号光传输效率降低。针对这一问题,文中搭建了信号光纤熔接的芯径失配功率损耗模型,简析了光纤熔接时芯径失配与信号光功率损耗的关系。设计了一套泵浦信号反向合束器信号光功率损耗测试系统。提出了一种通过优化反向合束器信号光纤参数,提升反向泵浦信号合束器的信号光功率传输效率的方法,并通过预拉锥工艺,制作出一支25/400 (6+1)×1反向合束器,经测试,信号光传输效率优于98%,实验室使用该反向合束器搭建了一台MOPA结构光纤激光放大器,实现了3 kW稳定输出。In the manufacturing process of the backward pump-signal combiner(BPSC) in high-power fiber lasers, the core diameter of the output signal fiber becomes thinner after being tapered, and the mode field mismatch occurs when splicing with the input signal fiber, which decreases the signal light transmission efficiency of BPSCs. To solve this problem, a simulation model was established to simplify the relationship between transmission efficiency and the mode field mismatch. A test system was built to measure the signal light transmission efficiency of backward pump-signal combiners. Finally, a method was proposed to enhance the signal power transmission efficiency of the BPSC through optimizing the parameters of its signal fiber.Accordingly, a(6+1)×1 BPSC using customized 25/400 double-cladding fibers was fabricated with a pre-tapering method, and its signal light transmission efficiency was better than 98% after being tested. Using this combiner, a bi-direction-pumping master oscillator power amplifier(MOPA) fiber laser system was built, achieving a stable output of 3 kW.

关 键 词：反向泵浦信号合束器(BPSC) 芯径失配 信号光传输效率 光强分布 

分 类 号：TN248.1[电子电信—物理电子学]