MODELING THE CONTROLLABILITY OF CHARACTERISTICS OF PLASMON GRAPHENE NANOANTENNA GRATINGS IN THE MID-IR RANGE

Abstract

Background. The introduction of nanoantennas for optical wireless communications in the infrared (IR) and visible bands enables higher data rates while reducing antenna size. The ability to tune the characteristics of graphene by chemical doping or bias voltage is relevant in the development of reconfigurable nanoantennas. The goal of the work is to study the characteristics (S-parameters, radiation patterns (RP)) of plasmonic graphene nanoantenna (PGNA) arrays, their controllability and the possibility of frequency scanning when changing the chemical potential of graphene (by applying an external electric field) in the mid-IR range. Matherials and methods. The use of graphene, which has good electrical conductivity, controlled conductivity and plasmonic properties in the terahertz (THz), far-IR and mid-IR ranges, is one of the most promising alternatives to noble metals (Au and Ag) as plasmonic materials at optical frequencies only. Modeling of the characteristics of PGNA arrays was carried out using the electrodynamic modeling program CST Microwave Studio 2019, which makes it possible to solve scientific problems associated with the design of graphene antennas in the IR wavelength range. Results. The results of modeling the controllability of the characteristics (S-parameters, DP) of a element of the antenna array (PGNA of rectangular geometry) and PGNA arrays at the resonant frequencies of the fundamental mode of surface plasmon polaritons (SPP) are obtained and the possibility of scanning in frequency when changing the chemical potential of graphene (by applying an external electric fields) in the mid-IR range. Conclusions. From the results of modeling the characteristics of PGNA arrays, it follows that with an increase in the chemical potential of graphene (in the range of values 0,3–1 eV), the operating frequencies are adjusted (frequency scanning) in the mid-IR range, the gain of the PGNA array increases, the RP main lobe narrows, and the RP side lobe level decrease; with an increase in the number of single elements (N = 256), the levels of the RP side lobes decrease and better controllability of the RP main lobe is observed.

Keywords

• mid-ir range
• plasmonic graphene nanoantenna arrays
• chemical potential
• radiation pattern
• frequency scanning