Smart Graphene-Based Frequency Selective Surface Designed to Act as Single or Dual Band Device with Reconfigurable Operation Bands

Abstract In this paper, a finite-difference time-domain (FDTD) formulation, based on the exponential matrix and on thin material sheet methods is developed for modeling subcellular thin graphene sheets. This formulation is validated by reproducing graphene frequency selective surfaces (FSS) known from literature. Then, we propose in this work a smart graphene FSS device. Smartness is obtained by means of a unity cell formed by a graphene ring with a graphene sheet placed in its aperture. By properly regulating the chemical potentials of the graphene elements, two frequency- tunable modus operandi are obtained: single- or dual-band rejection modes. When the device operates in its dual-band rejection mode, either of the rejection bands can be shifted individually in the frequency spectrum. Additionally, both rejection bands can also be reconfigured simultaneously.

摘要：本文针对亚细胞尺度超薄石墨烯片的建模问题，提出了一种基于指数矩阵与薄层材料法的时域有限差分法（Finite-Difference Time-Domain，FDTD）建模公式。通过复现文献中已报道的石墨烯频率选择表面（Frequency Selective Surfaces，FSS），对该建模公式进行了有效性验证。随后，本文提出一款智能石墨烯FSS器件。该器件的智能特性由一款由石墨烯环及其孔径内嵌石墨烯片构成的单元胞（Unity Cell）实现。通过精准调控各石墨烯单元的化学势，可获得两种频率可调的工作模式：单频带抑制模式与双频带抑制模式。当器件工作于双频带抑制模式时，两个抑制频带均可单独在频谱中进行频移调整；此外，两个抑制频带还可同时进行重构配置。