New pulse dynamics, which generates time-stretched dissipative soliton, has been analyzed in theory and demonstrated in experiment. With introducing non-equilibrium saturable absorber (SA) into the laser cavity, the time-dependent loss of SA can balance the intracavity dispersion, while gain and nonlinearity assist to stabilize the pulse. The pulse envelop is in exact sech-shape and the duration can be stretched to sub-microsecond by the cavity dispersion. To verify the dynamics, a mode-locked Er-doped fiber laser (EDFL) is fabricated, in which a piece of Tm-doped fiber (TDF) serves as the non-equilibrium SA. The laser delivers stable nanosecond pulse and its temporal intensity is in exact sech 2 shape. The pulse duration is invariant with the pump power but determined by the cavity length. As large as 155nJ mode-locked pulse has been generated. Furthermore, such mode-locked pulse can serve as ideal pump source to optical parametric oscillators, and will have wide applications in optical communication, material processing and biomedicine technology.

中文翻译：

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反常色散腔光纤激光器中的Sech形时间拉伸耗散孤子


产生时间拉伸耗散孤子的新脉冲动力学已在理论上进行了分析并在实验中得到了证明。通过在激光腔中引入非平衡饱和吸收体（SA），SA的时间相关损耗可以平衡腔内色散，而增益和非线性有助于稳定脉冲。脉冲包络具有精确的 sech 形状，并且持续时间可以通过腔体色散延长至亚微秒。为了验证动力学，我们制造了锁模掺铒光纤激光器（EDFL），其中一块掺铥光纤（TDF）作为非平衡SA。激光提供稳定的纳秒脉冲，其时间强度精确为 sech 2 形状。脉冲持续时间与泵浦功率无关，但由腔长度决定。已产生高达 155nJ 的锁模脉冲。此外，这种锁模脉冲可以作为光参量振荡器的理想泵浦源，在光通信、材料加工和生物医学技术中具有广泛的应用。