百瓦级中红外光纤随机激光放大  

Hundred⁃Watt⁃Level Mid⁃Infrared Random Fiber Laser Amplifier

作　　者：高旺城 马瑞 全欣 陈宇[1] 范滇元[1] 刘军[1,2] Gao Wangcheng;Ma Rui;Quan Xin;Chen Yu;Fan Dianyuan;Liu Jun(International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology,Institute of Microscale Optoelectronics,Shenzhen University,Shenzhen 518060,Guangdong,China;Key Laboratory of High Power Laser and Physics,Chinese Academy of Sciences,Shanghai 201800,China)

机构地区：[1]深圳大学微纳光电子学研究院二维材料光电科技国际合作联合实验室,广东深圳518060 [2]中国科学院高功率激光物理重点实验室,上海201800

出　　处：《中国激光》2024年第5期12-18,共7页Chinese Journal of Lasers

基　　金：中国科学院高功率激光物理重点实验室开放基金(SGKF202107);广东省基础与应用基础研究基金(2022A1515010326,2021A1515011532,2020A1515110471,2020A1515111143);深圳市科技创新委员会优青项目(RCYX20210609103157071);深圳市科技创新委员会重点项目(JCYJ20220818100019040)。

摘　　要：中红外波段高功率激光光源在工业加工和生物医疗等领域中有着广泛的应用。报道了基于主振荡器功率放大器(MOPA)结构的百瓦级中红外连续波光纤随机激光器,获得了最高输出功率为100.40 W、斜率效率为47.8%、波长为1980 nm的连续波激光输出。得益于MOPA结构中光纤随机激光种子源在激光放大过程中的光谱带宽保持特性,100.40 W激光输出时的3 dB光谱带宽仅为~0.2 nm。激光器的短时时域强度波动和长时功率波动均表现出优良的稳定性。所提实验技术方案和实验结果有望进一步拓宽中红外高功率光纤随机激光器的应用范围。Objective High-power laser sources operating in 2-μm band are gaining traction due to their diverse applications,including laser scalpels,plastic welding,and free-space laser communication.Over the past decade,random fiber lasers(RFLs)have emerged as a focal point of interest.These lasers utilize randomly distributed Rayleigh scattering and nonlinear amplification,distinguishing them from traditional resonant cavity lasers.The defining features of RFLs are their open cavity structure and incoherent feedback,which result in modeless lasing and significant suppression of temporal dynamics.However,research on RFLs has primarily concentrated on the near-infrared band,specifically around 1.1μm and 1.5μm,due to challenges such as significant transmission loss and weaker Rayleigh scattering in mid-infrared silica-based optical fibers.Historically,RFLs in the mid-infrared band have only realized low power outputs.In this study,we introduce a high-power RFL operating at 2μm,utilizing the master oscillator power amplifier(MOPA)approach.Impressively,we realize a peak power of 100.40 W with an efficiency slope of 47.8%and a narrow 3 dB spectral width of approximately 0.2 nm.Methods Figure 1 depicts the experimental arrangement for a high-powered RFL using the MOPA design.The seed consists of a 793-nm laser diode(LD),a(2+1)×1 pump combiner,a 2.4-m long thulium-doped fiber,a 1980-nm FBG,a 200-m single-mode fiber(SMF),and an isolator(ISO).The 1980-nm FBG serves as a point reflector,selecting the wavelength and providing optical feedback,in tandem with the Rayleigh scattering in the extended SMF.An isolator at the SMF end prevents unwanted light reflection.The preamplifier stage consists of a 793-nm LD,(2+1)×1 pump combiner,a 2.4-m thulium-doped fiber,and an isolator.Its role is to enhance the seed laser output power to a specified threshold.Inserting a mode-field adaptor(MFA)between the preamplifier and main amplifier minimizes insertion loss due to mode mismatch among different fibers.The main amplifier takes the laser s

关 键 词：激光器 光纤随机激光器 高功率激光器 瑞利散射 中红外激光器 高稳定性 

分 类 号：O436[机械工程—光学工程]