CAJ | 학술논문

设计了一种基于色散控制的相位调制锁模掺镱光纤激光器。针对相位调制锁模中模式跳变现象，基于非线性薛定谔方程，建立了光脉冲在光纤激光器系统中演变的数学模型，通过数值仿真研究了色散对脉冲稳定性的影响。在光纤环形腔中加入光子晶体光纤实现色散补偿，解决了输出脉冲在两个相位差为π的模式间跳变引起的不稳定问题。在稳定锁模的前提下，进一步分析了激光器关键参数（非线性系数、小信号增益系数、调制频率和调制深度）对输出脉冲时域特性的影响。结果表明，在腔内平均色散为－19 ps2／km 时，激光器工作在稳定锁模区域，产生重复频率4．918 GHz，脉宽2．54 ps 的锁模脉冲，这对于后续实验中的优化设计具有指导性意义。
설계료일충기우색산공제적상위조제쇄모참의광섬격광기。침대상위조제쇄모중모식도변현상，기우비선성설정악방정，건립료광맥충재광섬격광기계통중연변적수학모형，통과수치방진연구료색산대맥충은정성적영향。재광섬배형강중가입광자정체광섬실현색산보상，해결료수출맥충재량개상위차위π적모식간도변인기적불은정문제。재은정쇄모적전제하，진일보분석료격광기관건삼수（비선성계수、소신호증익계수、조제빈솔화조제심도）대수출맥충시역특성적영향。결과표명，재강내평균색산위－19 ps2／km 시，격광기공작재은정쇄모구역，산생중복빈솔4．918 GHz，맥관2．54 ps 적쇄모맥충，저대우후속실험중적우화설계구유지도성의의。
A kind of frequency-modulation mode-locked ytterbium-doped fiber laser is designed.Focused on mode-hopping phenomenon in frequency-modulation mode-locked pattern,the mathematical model of light pulse evolution in fiber laser is established based on nonlinear Schr?dinger equation,and the effects of dispersion on the pulse stability are studied through numerical simulation.The mode hopping problem,that output pulses tend to jump back and forth between two modes which are 1 80°apart relative to each other,is solved by employing a photonic crystal fiber in the ring cavity for dispersion compensation.In the premise of stable mode-locking,the effects of several critical parameters (such as the nonlinear coefficient,the small signal gain coefficient,the modulation frequency and the modulation depth)on time-domain characteristics of the output pulses are analyzed.The analytical result shows that the fiber laser works in stable mode-locking region and produces stable output pulses with 2.54 ps pulse width and 4.91 8 GHz repe-tition frequency when the average dispersion is -1 9 ps2 /km.The simulation data play a guiding role in optimal design for the later experiments.