Effective suppression of mode distortion induced by amplifiers stimulated Raman scattering in high-power fiber  

作　　者：Wei Gao Wenhui Fan Pei Ju Gang Li Yanpeng Zhang Aifeng He Qi Gao Zhe Li 

机构地区：[1]State Key Laboratory of Transient Optics and Photonics,Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi’an 710119,China [2]Key Laboratory for Physical Electronics and Devices of the Ministry of Education&Shaanxi Key Laboratory of Information Photonic Technique,Xi’an Jiaotong University,Xi’an 710049,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Key Laboratory on Applied Physics and Chemistry,Shaanxi Applied Physics and Chemistry Research Institute,Xi’an 710061,China [5]Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,China

出　　处：《High Power Laser Science and Engineering》2021年第2期135-141,共7页高功率激光科学与工程（英文版）

基　　金：National Natural Science Foundation of China(Nos.62005310 and 61675230);Equipment Pre-research Foundation of China(No.61406190302);Key R&D Program of Shaanxi Province(No.2018ZDXMGY-060);National Key R&D Program of China(No.2017YFB1104400).

摘　　要：Mode distortion induced by stimulated Raman scattering(SRS)has become a new obstacle for the further development of high-power fiber lasers with high beam quality.Here,an approach for effective suppression of the SRS-induced mode distortion in high-power fiber amplifiers has been demonstrated experimentally by adjusting the seed power(output power of seed source)and forward feedback coefficient of the rear port in the seed source.It is shown that the threshold power of the SRS-induced mode distortion can be increased significantly by reducing the seed power or the forward feedback coefficient.Moreover,it has also been found that the threshold power is extremely sensitive to the forward feedback power value from the rear port.The influence of the seed power on the threshold power can be attributed to the fact that the seed power plays an important role in the effective length of the gain fiber in the amplifier.The influence of the forward feedback coefficient on the threshold power can be attributed to the enhanced SRS configuration because the end surface of the rear port together with the fiber in the amplifier constitutes a half-opening cavity.This suppression approach will be very helpful to further develop the high-power fiber amplifiers with high beam quality.

关 键 词：high-power fiber amplifiers mode distortion stimulated Raman scattering SUPPRESSION 

分 类 号：TN248[电子电信—物理电子学] TN722