基于SOI片上光互连的等离子体准连续谱束缚态光学传感研究

等离子体传感技术是最有潜力可以打破衍射极限，实现超高灵敏度片上光传感的方案之一。但介电损耗大，品质因子小是其应用中的瓶颈。针对上述问题，本项目提出了等离子体与准连续谱束缚态相结合的片上光传感方案，拟构建类似于超腔的介质-金属混合型等离子体谐振腔，通过控制材料比例，优化结构参数激发高品质因子、低损耗的等离子体准连续谱束缚态，并结合Si波导及新型模斑转换器实现片上光子-等离子互连，研制出适用于光纤系统的高性能等离子体准连续谱束缚态光传感芯片。本项目将主要研究等离子体准连续谱束缚态的物理机制，集成化方案以及光学传感特性，为基于准连续谱束缚态的集成光电器件的研究提供理论与实验依据。

Plasmonic sensing technology is one of the most promising solutions that can break the diffraction limit and achieve the ultra-sensitive on-chip optical sensing. However, the bottleneck is that the plasmonics own large dielectric losses and small quality (Q) factors, limiting the practical applications. Addressing the above problems, this project proposes an on-chip optical sensing scheme that combines plasmonics with quasi-bound states in the continuum (BICs). Here, a supercavity-like insulator-metal hybrid plasmonic cavity is proposed. It is expected to achieve high Q-factor and low-loss plasmonic quasi-BICs in such cavity by optimizing the structural parameters and the material ratios. We will adopt Si waveguides as well as novel spot-size converters to combine with the proposed plasmonic cavity to realize chip-scale photonic-plasmonic hybrid interconnections, and develop a high-performance plasmonic quasi-BIC-based chip-integrated optical sensor which is compatible with fiber network systems. This project will mainly investigate the physical mechanisms, the integration schemes and the sensing characteristics of the plasmonic quasi-BICs, providing theoretical and experimental basis for the study of quasi-BIC-based integrated optoelectronic devices.