Brightness enhancement on random-distributed-feedback Raman fiber lasers pumped by multimode diodes  

作　　者：Xiulu Hao Chenchen Fan Yang Li Zhiyong Pan Jinyong Leng Tianfu Yao Bing Lei Pu Zhou 

机构地区：[1]College of Advanced Interdisciplinary Studies,National University of Defense Technology,Changsha,China [2]Nanhu Laser Laboratory,National University of Defense Technology,Changsha,China

出　　处：《High Power Laser Science and Engineering》2024年第3期69-76,共8页高功率激光科学与工程（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.62061136013 and 12174445)。

摘　　要：The power scaling on short wavelength(SW)fiber lasers operating around 1μm are in significant demand for applications in energy,environment and industry.The challenge for performance scalability of high-power SW lasers based on rare-earth-doped fiber primarily lies in the physical limitations,including reabsorption,amplified spontaneous emission and parasitic laser oscillation.Here,we demonstrate an all-fiberized,purely passive SW(1018 nm)randomdistributed-feedback Raman fiber laser(RRFL)to validate the capability of achieving high-power output at SWs based on multimode laser diodes(LDs)direct pumping.Directly pumped by multimode LDs,the high-brightness RRFL delivers over 656 W,with an electro-optical efficiency of 20%relative to the power.The slope efficiency is 94%.The beam quality M2factor is 2.9(which is~20 times that of the pump)at the maximum output signal power,achieving the highest brightness enhancement of 14.9 in RRFLs.To the best of our knowledge,this achievement also represents the highest power record of RRFLs utilizing multimode diodes for direct pumping.This work may not only provide a new insight into the realization of high-power,high-brightness RRFLs but also is a promising contender in the power scaling of SWs below 1μm.

关 键 词：fiber laser purely passive gain random distributed feedback stimulated Raman scattering 

分 类 号：TN248[电子电信—物理电子学]