Manipulation of Electromagnetic Waves Via Graphene-Based Coding Metamaterials for Terahertz Applications

Document Type : Original Article


1 Department of Communications, Faculty of Electronic Engineering, Menoufia University

2 Department of Communications, Faculty of Electronic Engineering< Menoufia University


This paper is concerned with the manipulation of electromagnetic waves in the Terahertz range using graphene. Graphene has the great advantage that its conductivity can be controlled via an electric bias. A unit cell constructed from two square rings enclosing a square patch made of graphene was simulated using HFSS that gives a reflection phase of 0 or π according to the bias. Scattering from a coding metamaterial in the form of a square matrix of 8x8 unit cells was analyzed. A plane wave incident normally on the coding metamaterial is scattered and formed two or four main beams according to the arrangement of unit cells. The unit cells are arranged as groups. The group may be a column or square. The groups alternate as 1x1, which means one group gives zero reflection phase and the next group gives π phase. Arrangements 1x1, 2x2, and 4x4 were studied. The beamwidth and direction of propagation of the scattered beams depend upon the arrangement of the groups (1x1, 2x2, or 4x4). The positions of scattered beamwidths in azimuth are fixed, they do not change with arrangement of groups. The elevation angle of the beams change from large value for 1x1 to smaller value for 4x4. In the limit when all the cells become of the same type , the elevation angle becomes zero and we have only one beam normal to the structure.