We investigated the resonance splitting in microring resonators (MRRs) constructed from nanofibers of organic dye, which function as active waveguides. The MRRs were fabricated by connecting both end parts of a nanofiber so that they contacted with each other in a side-by-side manner with a contact length of ∼5μm by micromanipulation on a substrate. We observed that the shape and width of the resonance peaks were sensitively changed by changing the contact length. Moreover, the resonance peaks split into a doublet by tuning the contact length. We propose that the splitting is due to the coupling between the counterclockwise and clockwise traveling modes within a ring. The coupling can be induced by the reflection of traveling light at the end faces of the nanofiber in the connection region. Since this mechanism leads to a strong mode coupling, the resonance splitting is resolved even though the resonance peaks of the nanofiber MRRs are relatively broad (the Q-factors of up to ∼2000).

我们研究了由有机染料纳米纤维构成的微环谐振器 (MRR) 中的共振分裂，其用作有源波导。MRRs 是通过连接纳米纤维的两端部分制成的，使它们以约 5 μ的接触长度并排方式相互接触m 通过在基板上进行显微操作。我们观察到共振峰的形状和宽度通过改变接触长度而敏感地改变。此外，通过调整接触长度，共振峰分裂成双峰。我们提出分裂是由于环内逆时针和顺时针行进模式之间的耦合。耦合可以通过连接区域中纳米纤维端面处行进光的反射引起。由于这种机制导致强模式耦合，即使纳米纤维 MRR 的共振峰相对较宽（Q因子高达 ~2000），共振分裂也得到解决。