Deng Decai, Zhang Haitao, Zu Jiaqi, Chen Junyu
Opt Lett. 2021 Apr 1;46(7):1612-1615. doi: 10.1364/OL.421697.
A pulsating soliton exists in various passively mode-locked fiber lasers. Versatile categories of pulsating solitons have been investigated in a steady regime. However, the formation dynamics of pulsating solitons have not been fully revealed. Herein, we experimentally captured both single pulsating soliton and two pulsating soliton formation processes in an all-normal-dispersion laser. With the help of the time-stretch dispersion Fourier transform technique, the real-time temporal and spectral evolutions of pulsating solitons, during the buildup process, were investigated. It is found that pulsation directly derives from the background noise. In addition, both types of pulsations experience several characteristic stages, including an unstable -switch, spectral shaping, broadening, oscillating, and narrowing, which might be induced by the transient non-balance between the gain and loss of the cavity. We anticipate that the work in this Letter can improve the understanding of pulsating behaviors and bring new insights into the dynamic phenomenon of nonlinear optical systems.
脉冲孤子存在于各种被动锁模光纤激光器中。在稳定状态下，人们已经对多种类型的脉冲孤子进行了研究。然而，脉冲孤子的形成动力学尚未完全揭示。在此，我们通过实验捕获了全正色散激光器中单个脉冲孤子和两个脉冲孤子的形成过程。借助时间拉伸色散傅里叶变换技术，研究了脉冲孤子在形成过程中的实时时间和光谱演化。研究发现，脉冲直接源于背景噪声。此外，两种类型的脉冲都经历了几个特征阶段，包括不稳定切换、光谱整形、展宽、振荡和变窄，这可能是由腔内增益和损耗之间的瞬态不平衡引起的。我们预计，本文的工作可以增进对脉冲行为的理解，并为非线性光学系统的动态现象带来新的见解。
