A plasmonic refractive index nanosensor based on Fano resonance was designed, the excellent performance of the structure was numerically achieved. The system consists of a metal–insulator-metal (MIM) waveguide with two silver baffles and a coupled split ring resonator (SRR), and the finite-difference time-domain (FDTD) method was utilized to study the transmission characteristics of the structure. The results show that the designed structure can excite the triple Fano resonance phenomenon. For a positive SRR structure, the transmission peak can be tuned vertically and horizontally by adjusting the structural parameters. Furthermore, the sensitivity of nanosensors can reach 1034 nm/RIU, and the maximum figure of merit (FOM) is 7.01 × 10⁴. Interestingly, the improved symmetrical SRR structure demonstrated that the sensitivity is as high as 1053 nm/RIU, and the maximum FOM value was 1.82 × 10⁵. High performance and good controllability can provide a new possibility for the design and optimization of nanosensor.

设计了一种基于Fano共振的等离子体折射率纳米传感器，在数值上实现了该结构的优异性能。该系统由带有两个银挡板的金属-绝缘体-金属（MIM）波导和一个耦合裂环谐振器（SRR）组成，并利用有限差分时域（FDTD）方法研究该结构的传输特性. 结果表明，所设计的结构可以激发三重法诺共振现象。对于正 SRR 结构，可以通过调整结构参数来垂直和水平调整传输峰值。此外，纳米传感器的灵敏度可达1034 nm/RIU，最大品质因数（FOM）为7.01 × 10 ⁴. 有趣的是，改进的对称 SRR 结构表明灵敏度高达 1053 nm/RIU，最大 FOM 值为 1.82 × 10 ⁵。高性能和良好的可控性可以为纳米传感器的设计和优化提供新的可能性。