Dynamic beam-steering of graphene-based terahertz cross Yagi–Uda antenna with a theoretical approach

Abstract

In this paper, for the first time, a dynamic tunable graphene-based cross Yagi–Uda antenna in the terahertz region has been investigated comprehensively by two numerical methods and analytical analysis. To verify the accuracy of the analytical solution based on the coupled dipole method to obtain the directivity pattern, two numerical methods of finite-element and finite-difference time-domain have been used. Numerical results are well matched with the theoretical ones. By introducing the tunable cross Yagi–Uda antenna with graphene-coated spheres, different directivity radiation patterns such as omni-, vertical and horizontal bi- and quad-directional have been obtained with the maximum directivities of 2.42, 12.4, 12.3, and 10.5 dBi, respectively. Moreover, the effect of different element shapes including cube and cylinder on the directivity and radiation efficiency has been studied. Also, the new idea of multiple-access and controlling the user’s access to the radiated optical electromagnetic waves from the transmitting antenna has been studied as an optical wireless on-chip link. Finally, the effect of structural parameters on the directivity of the proposed antenna has been surveyed with the tolerance of ±5% to investigate the imperfections that may appear in the fabrication process.

Theoretical analysis of a graphene quantum well hybrid plasmonic waveguide to design an inter/intra-chip nano-antenna

“…Recently, multi-beam reconfigurable plasmonic nano-antennas based on graphene have attracted tremendous attention due to the unique features of graphene as a promising two-dimensional (2D) monoatomic layer of carbon atoms in optical and terahertz (THz) frequency range for electronic and photonic applications [3,[23][24][25][26][27]. Graphene with its inherent tunability is a good candidate for reconfigurable and intelligent multi-beam nano-antennas because of its high conductivity and little skin effect in THz spectrum and high absorptive feature in visible and near-infrared spectra [25,28].…”

“…Finally, to investigate the possibility of fabrication process, a 5% tolerance for structural parameters and the effect of gold layer roughness instead of ideal uniform one have been considered. Utilizing both methods of electron-beam lithography and lift-off can ease the fabrication possibility of the proposed nano-antenna [12,23]. Moreover, to describe the practical characteristic of the proposed graphene quantum well HPWA, the effect of gold layer roughness has been studied instead of ideal uniform one.…”