基于光纤可调滤波器的1024 nm锁模脉冲产生与放大研究  

Generation and Amplification of a 1024 nm Mode-Locked Laser Based on a Tunable Fiber Filter

作　　者：崔友硕 张璐璐[1] 殷杰 董自凯 华玲玲[1] 田金荣[1] 宋晏蓉[1] Cui Youshuo;Zhang Lulu;Yin Jie;Dong Zikai;Hua Lingling;Tian Jinrong;Song Yanrong(Faculty of Science,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学理学部,北京100124

出　　处：《中国激光》2021年第5期234-242,共9页Chinese Journal of Lasers

基　　金：国家重点研发计划重点专项(2017YFB0405200);国家自然科学基金(61975003);北京市自然科学基金(4192015)。

摘　　要：1024 nm波长的脉冲激光在角分辨光电子能谱测量等领域有着不可或缺的用处,因此采用基于非线性偏振旋转(NPR)锁模的全正色散掺镱光纤激光器作为种子源,搭建了包含光纤可调滤波器的主振荡功率放大系统,实现了1024 nm激光放大输出。理论上基于金斯伯格-朗道方程模拟了NPR锁模的耗散孤子脉冲演化过程,实验上获得了耗散孤子脉冲输出,并且研究了锁模脉冲的建立过程,将其与理论仿真结果相比,结果基本吻合。通过可调滤波器对种子光进行滤波,并进行预放大及放大实验,当放大级泵浦功率为5 W时,得到中心波长为1024 nm、平均功率为1.1 W、脉冲能量为51 nJ、重复频率为21.5 MHz、信噪比为67.5 dB的稳定锁模脉冲输出。Objective Angular-resolved photoemission spectroscopy(ARPES)is a powerful and unique technique used to study the electron structure in condensed matter.It can directly obtain the energy band structure and electron self-energy by momentum resolution.A 1024 nm laser can be used as an ARPES source after multiple frequency doubling,such as the measurement of charge density wave gaps of telluride of rare earth elements.The main emission peak of Yb3+ions is near 1064 nm;hence,the emission of the 1024 nm pulse laser is relatively difficult,requiring the fine control of the filter parameters.Thus far,reports on the 1024 nm laser are mainly concentrated on solid-state lasers.A fiber laser has the advantages of compact structure,low cost,and good stability.The low output power of the fiber laser can be made up by the amplifier,which has a good application value.Methods In this study,pulse evolution in a fiber laser was numerically simulated by the system of the coupled Ginzburg-Landau equation and solved using the split-step Fourier method.The laser passed through each device in turn in the cavity and repeatedly circulated.The pulse formation and evolution were simulated.Experimentally,the seed source was an all-normal dispersion Yb-doped fiber laser mode-locked by nonlinear polarization rotation(NPR).The oscillator consisted of a 976 nm pump,a 980/1030 nm wavelength division multiplexer(WDM),apiece of54 cm Yb-doped fiber(YDF),an isolator polarization-independent isolator,an output coupler,and an NPR saturable absorber.A master oscillator power amplifier system based on a tunable fiber filter was built to realize the 1024 nm output laser.The seed pulse was filtered by a tunable filter.Subsequently,preamplification and amplification experiments were conducted.The preamplifier contained a pump,a WDM,apiece of YDF,and an isolator,while the amplifier comprised a pump,a WDM,and a piece of YDF.The laser was output by a collimating isolator.The output laser parameters were measured by a 12.5 GHz photoelectric detector,a 6 GHz osc

关 键 词：激光器 光纤激光器 锁模激光器 激光放大器 非线性偏振旋转 耗散孤子 

分 类 号：TN248[电子电信—物理电子学]