College of Physics, Mechanical and Electrical Engineering, Jishou University, Jishou, 416000, China.
National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yu Tian Road, Shanghai, 200083, China.
Sci Rep. 2017 Sep 6;7(1):10639. doi: 10.1038/s41598-017-10626-1.
Tunable and high-sensitivity sensing based on Fano resonance is analytically and numerically investigated in coupled plasmonic cavities structure. To analyze and manipulate the Fano line shape, the coupled cavities are taken as a composite cavity that supports at least two resonance modes. A theoretical model is newly-established, and its results agree well with the finite difference time domain (FDTD) simulations for the plasmonic stub-pair structure. The detection sensitivity factor in coupled cavities approaches 6.541 × 10 m, which is an order of magnitude larger than single stub case. In addition, the wavelengths of resonant modes in the plasmonic stub-pair structure can be adjusted independently, which paves a new way for improving detection sensitivity. These discoveries hold potential applications for realizing tunable and highly integrated photonic devices.
基于 Fano 共振的可调谐和高灵敏度传感在耦合等离子体腔结构中进行了分析和数值研究。为了分析和控制 Fano 线型，将耦合腔作为支持至少两个共振模式的复合腔。建立了一个新的理论模型，其结果与等离子体短截线对结构的有限差分时域（FDTD）模拟吻合较好。在耦合腔中，检测灵敏度因子接近 6.541×10^-7m，比单短截线情况大一个数量级。此外，等离子体短截线对结构中的共振模式的波长可以独立调节，为提高检测灵敏度开辟了新途径。这些发现为实现可调谐和高度集成的光子器件提供了潜在的应用。
