Yang Mingxiang, Han Shaoshuai, Gao Hongxia, Fang Kangwei, Zhang Shanshan, Liu Yutong, Yan Yunjie, Hao Xiaolei, Zhao Mingshan, Wu Zhenlin
Opt Lett. 2024 Oct 1;49(19):5603-5606. doi: 10.1364/OL.536732.
Integrated microring resonators (MRRs) on silicon on insulator (SOI) are attractive candidates for excellent performance sensing systems. In this work, a novel, to the best of our knowledge, subwavelength grating waveguide racetrack microring resonator (SWGW-RMRR) on SOI with high-sensitivity and wide-range refractive index (RI) sensing is proposed and demonstrated experimentally. Owing to the exceptional evanescence field of the Bloch mode for the SWGW, the SWGW-RMRR provides highly sensitive RI sensing. Meanwhile, the SWGW-RMRR makes the free of free spectral range (FSR) limitation on the detection range (DR) by monitoring the envelope spectrum. By combining the advantages of the evanescent field and envelope spectrum, a SWGW-RMRR sensor has been demonstrated with a RI sensitivity of 860.8 nm/RIU, a limit of the detection value of 1.9 × 10 RIU, and a wide range of detection range. The measured Q-factor of the SWGW-RMRRs with an 88.8 µm total cavity length is 6200. This work can successfully realize high-sensitivity and wide-range RI sensing, showing the promising applications of silicon photonics sensors on chips.
绝缘体上硅（SOI）上的集成微环谐振器（MRR）是高性能传感系统的理想候选者。在这项工作中，据我们所知，提出了一种新型的SOI上的亚波长光栅波导跑道微环谐振器（SWGW-RMRR），并通过实验进行了演示，该谐振器具有高灵敏度和宽范围的折射率（RI）传感特性。由于SWGW的布洛赫模式具有特殊的倏逝场，SWGW-RMRR提供了高灵敏度的RI传感。同时，SWGW-RMRR通过监测包络谱消除了检测范围（DR）上的自由光谱范围（FSR）限制。通过结合倏逝场和包络谱的优点，已证明SWGW-RMRR传感器的RI灵敏度为860.8 nm/RIU，检测值极限为1.9×10 RIU，检测范围宽。总腔长为88.8 µm的SWGW-RMRR的测量品质因数为6200。这项工作可以成功实现高灵敏度和宽范围的RI传感，展示了硅光子学芯片传感器的广阔应用前景。
