Kelly sidebands are a special type of dispersive wave that appear in mode-locked systems and they have recently been observed by pulsed excitation in integrated microcombs. Here, Kelly sidebands are generated by continuous-wave excitation in a partially coupled racetrack-resonator microcomb. The coupled-racetrack system supports two optical bands so that, in contrast to earlier studies, the soliton and Kelly sideband reside in distinct bands. The resulting interband excitation of the Kelly sidebands relaxes power requirements and continuous-wave sideband excitation is demonstrated. Tuning of sideband spectral position under pulsed excitation is also studied. Numerical simulation and the experiment show that the sidebands rely upon symmetry breaking caused by partial coupling of the two-ring system. More generally, multiband systems provide a new way to engineer Kelly sidebands for spectral broadening of microcombs.

中文翻译：

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耦合环孤子微梳中带间凯利边带的观测


凯利边带是锁模系统中出现的一种特殊类型的色散波，最近通过集成微梳中的脉冲激励观察到了它们。这里，凯利边带是通过部分耦合的跑道谐振器微梳中的连续波激励产生的。耦合跑道系统支持两个光学波段，因此与早期研究相比，孤子和凯利边带位于不同的波段。由此产生的凯利边带的带间激励放宽了功率要求，并且演示了连续波边带激励。还研究了脉冲激励下边带光谱位置的调谐。数值模拟和实验表明，边带依赖于两环系统部分耦合引起的对称性破缺。更一般地说，多频带系统提供了一种设计凯利边带以展宽微梳光谱的新方法。