Beamforming of Electrically Tunable Plasmonic Graphene Strip Nanoantennas in the Terahertz, Far-Infrared, and Mid-Infrared Ranges

Abstract—The purpose of this work is to study, using automated modeling methods, the possibility of scanning in frequency and beamforming of plasmonic graphene strip nanoantennas, which are electrically tunable by varying the chemical potential of graphene in the terahertz (THz), far-, and mid-infrared (IR) ranges. Graphene, which has exceptional electromagnetic, mechanical, electrical, and thermal properties, is promising for reconfigurable THz antennas due to its high conductivity and tunability in the THz range. Modeling of the performances of THz plasmonic graphene strip nanoantennas for various values of chemical potential was carried out using the CST Microwave Studio 2023 software package. The results of modeling the controllability of the reflection coefficients at the input of the nanoantenna and the radiation pattern (RP) at the resonance frequencies of the fundamental mode of surface plasmon-polaritons (SPPs) and the second-order SPP mode were obtained when changing the values of the chemical potential (0.3–0.7 eV) in the THz, far-, mid-IR ranges. It follows from the modeling results that it is possible to tune operating frequencies (frequency scanning) from THz to the far- and mid-IR ranges and form a multibeam RP of reconfigurable graphene strip nanoantennas by changing the chemical potential of graphene (applying an external electric field) without changing their geometry and dimensions.