基于抛物线演化的宽光谱光纤啁啾脉冲放大系统  

Broadband Fiber Chirped-pulse Amplification System Based on Parabolic Evolution

作　　者：杜李 靳翠红 杨直[2] 崔玉栋 DU Li;JIN Cuihong;YANG Zhi;CUI Yudong(State Key Laboratory of Modern Optical Instrumentation,College of Optical Science and Engineering,Zhejiang University,Hangzhou 310027,China;Xi′an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi′an 710119,China;Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]浙江大学光电科学与工程学院现代光学仪器国家重点实验室,杭州310027 [2]中国科学院西安光学精密机械研究所,西安710119 [3]华中科技大学武汉光电国家研究中心,武汉430074

出　　处：《光子学报》2022年第11期124-131,共8页Acta Photonica Sinica

基　　金：浙江省自然科学基金(No.LGG20F050002);武汉光电国家研究中心开放基金(No.2020WNLOKF008)。

摘　　要：为了满足光纤激光器在宽光谱高能量应用领域的要求,搭建了一种结构紧凑的光纤型宽光谱啁啾脉冲放大系统。将色散管理型锁模激光器产生的高斯型脉冲作为种子源,注入到正色散掺铒光纤放大器中进行自相似放大,脉冲将逐渐演化成抛物线型,此过程中脉冲的谱宽和能量都迅速增大。随后脉冲经色散补偿光纤的时域展宽,双包层铒镱共掺光纤的功率放大,透射光栅对压缩后实现了高能量的宽光谱输出。并结合理论模拟,优化了激光器的各元件参数,最终在中心波长1 560 nm处实现了光谱宽度为30 nm,平均功率为1.3 W,脉宽为587 fs,重复频率为40.1 MHz的宽光谱高能量激光输出。该激光器结构紧凑,稳定性好,对光学频率梳、光通信等应用领域具有一定研究价值。Fiber lasers have attracted substantial research interest due to their high stability,excellent beam quality and system compactness.Furthermore,lasers generating high-energy ultrafast pulses and operating at the 1 550 nm region are widely developed due to the low optical attenuation at the first communication window and more cost-effective than other laser sources in a variety of applications such as ultrafast spectroscopy,precision material processing and terahertz-wave generation.To achieve high-energy pulses,an Erbium-doped fiber amplifier was employed to amplify seed pulses.However,pulses will accumulate large nonlinear effects such as Self-Phase Modulation(SPM) and Stimulated Raman Scattering(SRS)during direct amplification,thus degrading the pulse quality.One common solution is to widen the pulse width by introducing a chirp before amplification.The peak power intensity is significantly attenuated,avoiding excessive nonlinearity.The amplified pulse is then de-chirped by a compressor.This method is called Chirped Pulse Amplification(CPA).Several high-power CPA systems operating at1.56 μm have been demonstrated in recent years.However,all of these sources produced a pulse with spectral width between 5 nm and 15 nm.Broadband fiber laser plays an important role in optical frequency combs,optical coherent tomography,optical coherence radar and fiber optical sensing systems.There is a lack of high-energy devices capable of generating pulses with spectral width above 30 nm.Several approaches have been utilized to generate broadband pulses.A noise-like mode-locked fiber laser was demonstrated based on the precise adjustment of intracavity dispersion.However,this laser regime was seldom applied in ultrashort pulses due to its incompressibility.A Mamyshev oscillator is able to generate broadband pulses as shorter than 100 fs at the expense of complicated intracavity structure and accurate pulse evolution.The extra-cavity generation method relies on Highly Nonlinear Fibers(HNLFs),such as photonic crystal fibers,whose

关 键 词：啁啾脉冲放大 自相似放大 宽光谱 掺铒光纤 铒镱共掺光纤 

分 类 号：TN248[电子电信—物理电子学]