In this letter, we experimentally demonstrate various low-amplitude sub-pulses releasing from the rectangular-shaped noise-like pulses (NLPs) in a passively mode-locked fiber laser. Via incorporating a several hundred meters highly nonlinear fiber (HNLF) in the cavity, a series of continuous wave (CW) components are observed in the output optical spectrum, and sub-pulses formation results from the interactions among the CW components and the random ultrashort pulses in NLPs wave packet. A novel type of harmonic sub-pulses with 952.5874 MHz repetition rate is achieved, corresponding to the around 2994th harmonic of the fundamental cavity frequency. The obtained results contribute to further understanding the nature and formation mechanism of sub-pulses in NLPs regime.

中文翻译：

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被动锁模光纤激光器中类噪声脉冲释放的子脉冲


在这封信中，我们通过实验演示了被动锁模光纤激光器中矩形类噪声脉冲（NLP）释放的各种低幅度子脉冲。通过在腔体中加入数百米的高度非线性光纤（HNLF），在输出光谱中观察到一系列连续波（CW）分量，并且子脉冲的形成是由CW分量与随机超短波之间的相互作用产生的。 NLP 波包中的脉冲。实现了一种具有 952.5874 MHz 重复率的新型谐波子脉冲，对应于基腔频率的大约 2994 次谐波。所获得的结果有助于进一步理解 NLP 体系中子脉冲的性质和形成机制。