The engineering of metal-insulator-metal metasurfaces (MSs) displaying sharp spectral features based on Fano-type interference between a symmetric bright mode and an antisymmetric dark mode is reported. The proposed mechanism for direct excitation of antisymmetric mode avoids the necessity of mode hybridization through near-field coupling. Modeling and experimental results bring evidence that such MSs operating in the microwave or terahertz domains provide greater flexibility for Fano resonance engineering and provide strong enhancement of the spectral selectivity factor. It is shown that the occurring Fano resonance interference is related to the broken eigenmode orthogonality in open systems and is independent of hybridization mechanism.

中文翻译：

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通过直接激发反对称暗模式进行的高Q Fano共振

报告了基于对称亮模式和反对称暗模式之间的Fano型干涉的，显示尖锐光谱特征的金属-绝缘体-金属超表面（MSs）工程。所提出的用于直接激发反对称模式的机制避免了通过近场耦合进行模式杂交的必要性。建模和实验结果证明，在微波或太赫兹域中运行的此类质谱仪为Fano共振工程提供了更大的灵活性，并大大增强了光谱选择性因子。结果表明，在开放系统中发生的Fano共振干扰与本征模正交性的破坏有关，并且与杂交机制无关。