石墨烯纳米片阵列的表面等离激元法诺共振

为了在中红外波段获得多阶表面等离激元法诺共振, 设计了结构简单、制备方便的非对称石墨烯纳米片二聚体阵列超表面。采用有限元分析方法, 对各阶法诺共振峰产生的物理机制, 费米能级、纳米片结构及相对位置等因素对法诺共振的影响进行了理论分析。结果表明, 随着费米能级的增加, 法诺共振发生蓝移; 表面等离激元共振效应增强, 同时增强了近场的局域效应; 随着纳米片二聚体的大小和位置的不对称性增加, 法诺线型的非对称性也随之增加; 这种结构简单的多阶表面等离激元法诺共振有望在生物传感及相关领域得到广泛应用。该研究为进一步的实验研究提供了理论参考。

Plasmonic Fano resonance based on the graphene nanosheet array

In order to obtain strong multiple Fano resonances, a metasurface composed of asymmetric nanosheet heterodimer was designed in the paper. Based on the finite element analysis method, the physical mechanism of Fano resonances was analyzed by the hybridization theory, and the different Fano responses resulted from different Fermi levels, structures parameters were analyzed. Results show that when the Fermi level of the graphene nanosheet increases, the Fano resonance peaks blue shift, and the intensity of graphene responses is enhanced, which causes that the local effect and absorption are enhanced accordingly. At the same time, with the increase of the asymmetry of the size and position of the nanosheet heterodimer, the asymmetry of Fano resonances also increases. The Fano resonances based on the simply graphene nanosheet heterodimer array are expected to be widely used in biosensor and related fields. The study provides theoretical reference for further experimental research.