Coupled-Resonator-Induced Fano Resonances for Plasmonic Sensing with Ultra-High Figure of Merits
Coupled-Resonator-Induced Fano Resonances for Plasmonic Sensing with Ultra-High Figure of Merits
复制标题
用于具有超高品质因数的等离激元传感的耦合谐振器感应 Fano 谐振
DOI：
10.1007/s11468-013-9580-4
复制
发表时间：
2013-12-01
期刊：
影响因子：
3
通讯作者：
Gong, Qihuang
中科院分区：
文献类型：
--
作者：
Chen, Jianjun;Li, Zhi;Gong, Qihuang
法诺共振的数值预测超紧凑等离子体结构，包括金属-隔离器-金属（MIM）波导侧耦合两个相同的短截线谐振器。基于散射矩阵理论的解析模型和相对相位分析可以很好地解释这一现象。在传感应用中，该结构的灵敏度约为1.1 × 103 nm/RIU，在λ = 980 nm处的品质因数高达2 × 105，这是由于该结构在该波长处具有极低的透射率和尖锐的非对称Fano线形。这种等离激元结构具有很高的优值和仅约0.2 μ m2的基底面，可能在片上纳米传感器中有重要的应用。
Fano resonances are numerically predicted in an ultracompact plasmonic structure, comprising a metal-isolator-metal (MIM) waveguide side-coupled with two identical stub resonators. This phenomenon can be well explained by the analytic model and the relative phase analysis based on the scattering matrix theory. In sensing applications, the sensitivity of the proposed structure is about 1.1 × 103nm/RIU and its figure of merit is as high as 2 × 105at λ = 980 nm, which is due to the sharp asymmetric Fano line-shape with an ultra-low transmittance at this wavelength. This plasmonic structure with such high figure of merits and footprints of only about 0.2 μm2may find important applications in the on-chip nano-sensors.