摘要
The soliton spectral tunneling（SST） effect, as a soliton spectral switching phenomenon, enables a soliton to tunnel through a spectrally limited regime of normal dispersion in the fiber with multiple zero dispersion wavelengths（ZDWs）.Since initial chirp can affect the behavior of pulse evolution, we numerically study the influence of chirp on the SST in the process of supercontinuum（SC） occurring in a photonic crystal fiber（PCF） with three ZDWs. The linear chirp is imposed by a phase modulation of input pulse while maintaining a constant pulse duration. Interestingly, it is found that the spectral range and flatness can be flexibly tuned by adjusting the initial chirp value. More specifically, positive chirp facilitates soliton self-frequency shifting（SSFS）, making the soliton quickly transfer from one anomalous dispersion regime to another accompanied by the generation of dispersive waves（DWs）. In this case, the SST effect further expands the spectral range by enhancing both the red-shift of the fundamental soliton and the blue-shift of DWs, thus generating a broader SC. However, negative chirp suppresses the SST effect, resulting in a smoother SC at the expense of bandwidth.Therefore, the findings in this work provide interesting results relating to the influence of initial chirp on the SST to generate a considerably smoother and broader SC, which is extremely useful in many applications, such as wavelength conversion and SC generation.
The soliton spectral tunneling（SST） effect, as a soliton spectral switching phenomenon, enables a soliton to tunnel through a spectrally limited regime of normal dispersion in the fiber with multiple zero dispersion wavelengths（ZDWs）.Since initial chirp can affect the behavior of pulse evolution, we numerically study the influence of chirp on the SST in the process of supercontinuum（SC） occurring in a photonic crystal fiber（PCF） with three ZDWs. The linear chirp is imposed by a phase modulation of input pulse while maintaining a constant pulse duration. Interestingly, it is found that the spectral range and flatness can be flexibly tuned by adjusting the initial chirp value. More specifically, positive chirp facilitates soliton self-frequency shifting（SSFS）, making the soliton quickly transfer from one anomalous dispersion regime to another accompanied by the generation of dispersive waves（DWs）. In this case, the SST effect further expands the spectral range by enhancing both the red-shift of the fundamental soliton and the blue-shift of DWs, thus generating a broader SC. However, negative chirp suppresses the SST effect, resulting in a smoother SC at the expense of bandwidth.Therefore, the findings in this work provide interesting results relating to the influence of initial chirp on the SST to generate a considerably smoother and broader SC, which is extremely useful in many applications, such as wavelength conversion and SC generation.
作者
赵赛丽
杨华
赵奕霖
肖宇哲
Saili Zhao1,2, Huan Yang1,3, Yilin Zhao1, and Yuzhe Xiao4(1 College of Information Science and Engineering, Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education Hunan University, Changsha 410082, China 2Electrical Engineering Department, University of California, Los Angeles, California 90095, USA 3 Synergetic Innovation Center for Quantum Effects and Application, Hunan Normal University, Changsha 410082, China 4Department of Electrical Engineering, University of Wisconsin Madison, Madison, Wisconsin 53706, US)
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.61275137 and 61571186)
the Natural Science Foundation of Hunan Province,China(Grant No.2018JJ2061)
