干形腔耦合MIM波导的传感特性研究

Research on Sensing Characteristics of Chinese Word Gan Shaped Cavity Coupled MIM Waveguides

摘要: 光学微腔的共振耦合在微纳米器件领域非常重要。本文设计的是干形谐振腔和总线波导组成的微纳米结构，其运用时域有限差分法(FDTD)进行模拟计算，分析改变谐振腔与总线波导的耦合间距、谐振腔各支节的长度、腔内介质的折射率时的共振特性以及传感特性，同时还利用耦合模理论和驻波理论验证干形谐振腔和总线波导耦合现象的正确性。优化结构参数，得到结构的最大灵敏度为1444.5 nm/RIU，品质因素最大为68.78，在谐振腔内添加温敏材料，该结构可用于温度传感。最后，在总线波导同侧再添加一个干形结构形成干形腔的级联，出现类电磁感应透明现象，在慢光方面具有重要的应用。本文设计的干形谐振腔可为以后传感器提高灵敏度提供一定的价值参考。

Abstract: Resonant coupling of optical microcavities is very important in the field of micro-nano devices. In this paper, a micro-nano structure composed of a Chinese word gan shaped cavity and a bus waveguide is designed, and the finite difference time domain (FDTD) method is used to simulation calculations to analyze the coupling spacing between the resonator and the bus waveguide, the length of each branch of the resonator, the resonance characteristics and sensing characteristics of the refractive index of the medium in the cavity, at the same time, the coupling mode theory and standing wave theory are used to verify the correctness of the coupling phenomenon of dry resonators and bus waveguides. By optimizing the structural parameters, the maximum sensitivity of the obtained structure is 1444.5 nm/RIU, and the maximum quality factor is 68.78, by adding temperature-sensitive material in the resonant cavity, the structure can be temperature-sensing. Finally, a Chinese word gan shaped cavity is added on the same side of the bus waveguide to form a cascade of Chinese word gan shaped cavity, and the phenomenon of electromagnetic induction-like transparency appears, which has important applications in slow light. The Chinese word gan shaped cavity designed in this paper provides a certain value reference for improving the sensitivity of the sensor in the future.