Phase-matching-induced near-chirp-free solitons in normal-dispersion fiber lasers  

作　　者：Dong Mao Zhiwen He Yusong Zhang Yueqing Du Chao Zeng Ling Yun Zhichao Luo Tijian Li Zhipei Sun Jianlin Zhao 

机构地区：[1]Key Laboratory of Light Field Manipulation and Information Acquisition,Ministry of Industry and Information Technology,School of Physical Science and Technology,Northwestern Polytechnical University,710129 Xi’an,China [2]College of Electronic and Optical Engineering&College of Microelectronics,Nanjing University of Posts and Telecommunications,210046 Nanjing,China [3]Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices&Guangzhou Key Laboratory for Special Fiber Photonic Devices and Applications,South China Normal University,510006 Guangzhou,China [4]Department of Electronics and Nanoengineering and QTF Centre of Excellence,Aalto University,Aalto,Finland

出　　处：《Light(Science & Applications)》2022年第2期230-241,共12页光（科学与应用)（英文版）

基　　金：This work was funded by the National Key R&D Program of China under Grant No.2017YFA0303800;the National Natural Science Foundation of China under Grant No.11874300;11634010;the Fundamental Research Funds for the Central Universities under Grant No.3102019JC008,3102019PY002;the Natural Science Foundation of Shaanxi Province under Grant No.2019JQ-447.

摘　　要：Direct generation of chirp-free solitons without external compression in normal-dispersion fiber lasers is a long-term challenge in ultrafast optics.We demonstrate near-chirp-free solitons with distinct spectral sidebands in normaldispersion hybrid-structure fiber lasers containing a few meters of polarization-maintaining fiber.The bandwidth and duration of the typical mode-locked pulse are 0.74 nm and 1.95 ps,respectively,giving the time-bandwidth product of 0.41 and confirming the near-chirp-free property.Numerical results and theoretical analyses fully reproduce and interpret the experimental observations,and show that the fiber birefringence,normal-dispersion,and nonlinear effect follow a phase-matching principle,enabling the formation of the near-chirp-free soliton.Specifically,the phasematching effect confines the spectrum broadened by self-phase modulation and the saturable absorption effect slims the pulse stretched by normal dispersion.Such pulse is termed as birefringence-managed soliton because its two orthogonal-polarized components propagate in an unsymmetrical“X”manner inside the polarization-maintaining fiber,partially compensating the group delay difference induced by the chromatic dispersion and resulting in the selfconsistent evolution.The property and formation mechanism of birefringence-managed soliton fundamentally differ from other types of pulses in mode-locked fiber lasers,which will open new research branches in laser physics,soliton mathematics,and their related applications.

关 键 词：fiber POLARIZATION DISPERSION 

分 类 号：TN248[电子电信—物理电子学]