Pan Wei, Jin Liang, Wang Jiazhu, Wang Renyan, Zhang He, Yingtian Xu, Zhao Xin, Li Yang, Ma Xiaohui
Appl Opt. 2021 Feb 1;60(4):923-928. doi: 10.1364/AO.413601.
All-normal-dispersion (ANDi) dissipative soliton mode-locking is realized based on nonlinear multimode interference (NMI), which is implemented by offset-splicing three pieces of graded-index multimode fibers (GIMFs) and acts as a saturable absorber. The higher-order modes can be excited by offset-splicing GIMFs (OS-GIMFs), which eliminates adding the step multimode fiber (SIMF) into the resonant cavity and the precise length requirement of the SIMF. In the experiment, the stable dissipative soliton mode-locking at 1030 nm can be obtained with the pulse width of 7.3 ps and the repetition rate of 20.52 MHz, and the bandwidth is 6.98 nm. The maximum output is 3.2 mW with the pump power of 257 mW. The OS-GIMFs can significantly improve the saturated absorption and can easily realize dissipative soliton mode-locking in ANDi regions, which makes it attractive in ultrafast photonics.
基于非线性多模干涉（NMI）实现了全正色散（ANDi）耗散孤子锁模，该非线性多模干涉通过对三根渐变折射率多模光纤（GIMF）进行错位熔接来实现，并起到饱和吸收体的作用。通过对GIMF进行错位熔接（OS-GIMF）可以激发高阶模，这消除了将阶跃多模光纤（SIMF）添加到谐振腔中的需求以及对SIMF精确长度的要求。在实验中，可获得中心波长为1030 nm的稳定耗散孤子锁模，脉冲宽度为7.3 ps，重复频率为20.52 MHz，带宽为6.98 nm。泵浦功率为257 mW时，最大输出功率为3.2 mW。OS-GIMF可以显著提高饱和吸收，并能在ANDi区域轻松实现耗散孤子锁模，这使其在超快光子学领域具有吸引力。
