两种色散特异材料双层结构中的法诺共振机制

Fano Resonances in a Bilayer Structure Composed of two Kinds of Dispersive Metamaterials

单负特异材料双层结构中,由于分离式的反射共振和宽带的强反射之间发生的法诺型干涉,在反射谱中出现了非对称法诺谱。当光斜入射到单负特异材料异质结时,分离式的反射共振发生在单负特异材料色散磁导率接近于零的频率点。通过解析和数值分析得到,法诺型反射的非对称因子与入射角是密切相关的。

We theoretically find that a bi-layer structure composed of two kinds ofdispersive metamaterials can possess an asymmetric reflection spectrum due toFano-type interference between a discrete reflection resonance and a broadbandstrong reflection. The discrete reflection resonance appears at the frequency aroundwhich the dispersive permeability is near to zero at oblique incidence. Based onanalytical and numerical analysis, the asymmetric factor in the Fano-type reflection isfound to be linked with the angle of incidence.