Zhu Xiaoxiu, Xiong Xiao, Zhu Zhendong, Liu Wenjing, Cao Qi-Tao, Xiao Yun-Feng
State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, New Cornerstone Science Laboratory, School of Physics, Peking University, Beijing 100871, China.
Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
Phys Rev Lett. 2024 May 31;132(22):223801. doi: 10.1103/PhysRevLett.132.223801.
Hybrid microresonators have served an intriguing platform for fundamental research and applied photonics. Here, we study the plasmonics-engineered coupling between degenerate optical whispering gallery modes, which can be tuned in a complex space featuring the dissipative strong, dispersive strong, and weak coupling regimes. Experimentally, the engineering of a single plasmonic resonance to a cavity mode family is examined in a waveguide-integrated high-Q microdisk, from which the complex coupling coefficients are extracted and agree well with theoretical predictions. The coupling strength over 10 GHz is achieved for both dissipative and dispersive interactions, showing a remarkable enhancement compared to that induced by a dielectric scatterer. Furthermore, the far fields of hybridized cavity modes are measured, revealing the coherent interference between the radiative channels. Our results shed light on the engineering of whispering gallery modes through plasmonic resonances, and provide fundamental guidance to practical microcavity devices.
混合微谐振器为基础研究和应用光子学提供了一个引人入胜的平台。在此，我们研究了简并光学回音壁模式之间的等离激元工程耦合，这种耦合可以在一个具有耗散强耦合、色散强耦合和弱耦合区域的复杂空间中进行调谐。在实验中，我们在一个波导集成的高Q微盘中研究了将单个等离激元共振工程到一个腔模家族的过程，从中提取了复耦合系数，并且与理论预测结果吻合良好。对于耗散和色散相互作用，都实现了超过10 GHz的耦合强度，与由介电散射体引起的耦合强度相比有显著增强。此外，我们测量了杂化腔模的远场，揭示了辐射通道之间的相干干涉。我们的结果为通过等离激元共振对回音壁模式进行工程设计提供了启示，并为实际的微腔器件提供了基础指导。
