Advancements in computational capabilities along with the possibility of accessing high power levels have stimulated a reconsideration of multimode fibers. Multimode fibers are nowadays intensely pursued in terms of addressing longstanding issues related to information bandwidth and implementing new classes of high-power laser sources. In addition, the multifaceted nature of this platform, arising from the complexity associated with hundreds and thousands of interacting modes, has provided a fertile ground for observing novel physical effects. However, this same complexity has introduced a formidable challenge in understanding these newly emerging physical phenomena. Here, we provide a comprehensive theory capable of explaining the distinct Cherenkov radiation lines produced during multimode soliton fission events taking place in nonlinear multimode optical fibers. Our analysis reveals that this broadband dispersive wave emission is a direct byproduct of the nonlinear merging of the constituent modes comprising the resulting multimode soliton entities, and is possible in both the normal and anomalous dispersive regions. These theoretical predictions are experimentally and numerically corroborated in both parabolic and step-index multimode silica waveguides. Effects arising from different soliton modal compositions can also be accounted for, using this model. At a more fundamental level, our results are expected to further facilitate our understanding of the underlying physics associated with these complex “many-body” nonlinear processes.

计算能力的进步以及获得高功率水平的可能性已经激发了对多模光纤的重新考虑。在解决与信息带宽相关的长期问题和实施新型高功率激光源方面，多模光纤现在受到了强烈的追捧。此外，由于与成百上千的交互模式相关的复杂性，该平台的多面性为观察新的物理效应提供了沃土。然而，同样的复杂性给理解这些新出现的物理现象带来了巨大的挑战。这里，我们提供了一个综合理论，能够解释在非线性多模光纤中发生的多模孤子裂变事件期间产生的不同切伦科夫辐射线。我们的分析表明，这种宽带色散波发射是构成多模孤子实体的组成模式非线性合并的直接副产品，并且在正常和异常色散区域中都是可能的。这些理论预测在抛物线和阶跃折射率多模石英波导中都得到了实验和数值的证实。使用该模型还可以考虑由不同孤子模态组合引起的影响。在更基本的层面上，