高峰值功率GMN飞秒光纤激光器研究进展(特邀)  

Research progress on high peak power GMN femtosecond fiber lasers(invited)

作　　者：夏童 招赫 朱书缘 张鹏磊 曹思远 王璞[1,2,3] XIA Tong;ZHAO He;ZHU Shuyuan;ZHANG Penglei;CAO Siyuan;WANG Pu(Beijing Engineering Research Center of Laser Technology,Beijing University of Technology,Beijing 100124,China;Key Laboratory of Trans-scale Laser Manufacturing Technology,Beijing University of Technology,Beijing 100124,China;School of Physics and Optoelectronics Engineering,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学物理与光电工程学院,北京100124 [2]北京工业大学北京市激光应用技术工程技术研究中心,北京100124 [3]北京工业大学跨尺度激光成型制造技术教育部重点实验室,北京100124

出　　处：《红外与激光工程》2024年第10期1-18,共18页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(62035002)。

摘　　要：高峰值功率飞秒光纤激光器在高精度工业制造、生物医学、国防、航空航天等领域有着广泛的应用。目前,产生高峰值功率飞秒光纤激光的主要方法是啁啾脉冲放大技术和非线性脉冲放大技术,然而前者虽然能够产生单脉冲能量大于1 mJ的飞秒脉冲,但受限于增益窄化效应,产生的脉冲持续时间通常大于200 fs。后者虽然能够产生持续时间~50 fs的脉冲,但整体设计比较复杂,限制了其应用范围。随着国内外相关工作的长期积累以及激光器件等硬件能力的提升,科研人员提出了一种基于增益管理非线性(Gain-Managed Nonlinear,GMN)放大的方案,这项技术能够以简单的系统设计产生持续时间小于50 fs的脉冲,还能保证紧凑的系统结构。综述了增益管理非线性放大技术的理论研究进展,总结了国内外不同设计结构的增益管理非线性放大系统研究进展,最后对增益管理非线性放大系统的应用进行了展开分析,展望了其在未来的发展方向。进一步分析了泵浦波长、泵浦方式对增益管理非线性放大的影响,提出了一种全光纤一体化的增益管理非线性放大系统,并利用该系统进行了超连续谱产生的应用研究。Significance High-power Ytterbium-doped femtosecond fiber lasers have rapidly developed over the past few decades due to their all-fiber structural design,excellent beam quality,and reliable system stability.They are widely used in industrial processing,biomedicine,military defense,and frontier science.Fiber lasers utilizing chirped pulse amplification(CPA)technology are the predominant solution for these applications.Although fiber laser systems based on CPA are capable of generating femtosecond pulses with mJ level pulse energy,the pulse widths are typically above 200 fs.Nevertheless,a wide variety of applications require relatively low pulse energy and significantly shorter pulse durations.To date,the technique of nonlinear pulse amplification(NPA)has been employed to achieve femtosecond pulses with durations less than 50 fs.NPA technology includes self-similar pulse amplification,pre-chirp management amplification,and gain management nonlinear(GMN)amplification.In self-similar pulse amplification,however,the spectrum tends to exceed the gain bandwidth at higher energies,resulting in reduced pulse quality after compression.Pre-chirp managed amplification often requires precise control of the seed pulse dispersion,increasing system complexity and reducing stability.Compared to the first two technologies,GMN technology relies on nonlinear attractors and is insensitive to the temporal distribution of the seed pulse.Additionally,it surpasses the limitations of the gain narrowing effect,producing highly compressible pulses with spectral bandwidths exceeding hundreds of nanometers.Compared to CPA technology,the GMN technology does not require additional stretchers,ensuring an extremely compact structure.Progress Firstly,the mechanism of GMN amplification technology is detailed.GMN amplification primarily utilizes the dynamically evolving gain spectrum as a degree of freedom,generating spectra that far exceed the gain spectrum bandwidth while maintaining an approximately linear chirp and can be compressed to~50 fs.In

关 键 词：飞秒脉冲 高峰值功率 增益管理非线性放大 高紧凑性 高稳定性 

分 类 号：O436[机械工程—光学工程]