A Novel Approach for Modeling the Geometry and Constitutive Parameters of an Armchair Single-Wall Carbon Nanotube Antenna Operating in the NIR Regime

Abstract

This paper investigates the electromagnetic performance of an armchair, Single-Wall Carbon Nanotube (SWCNT) dipole antenna in the Near-Infra-Red (NIR) regime. Numerical analysis is performed using the Finite Integration Technique (FIT) formulation of the classical Maxwell's equations as implemented in the commercial software package CST MICROWAVE STUDIO® (CST MWS). Closed-form analytical expressions have been derived for the complex electrical conductivity and permittivity functions of the armchair SWCNT and validated against available experimental and simulated results for frequencies from 400 THz up to 625 THz. Geometrical dispersion is considered for the first time by modeling the hexagonal geometry of the armchair SWCNT. The length of the dipole antenna is 212 nm with a diameter of 1.36 nm. The first resonant mode of the armchair SWCNT antenna is found to be 282 THz. The corresponding resonant frequency of a solid and hollow circular cylindrical model of the same radius and length is 380 THz. The current distribution of the first resonant mode is found to be strongly damped at the ends of the SWCNT. General performance metrics of the nanoscale dipole antenna are presented, such as return loss expressed in terms of frequency spectrum of the S11 parameter, surface current, gain, radiation efficiency, and radiation patterns. The antenna performance is compared against SWCNT dipole antennas comprised of solid and hollow cylindrical geometries