Investigation of Copper and Carbon Nanotube Antennas using Thin Wire Integral Equations

In this paper we investigate the characteristics of extremely small carbon nanotube (CNT) dipole antennas on the basis of the thin wire Hallen integral equation. As a reference a thin copper wire antenna is investigated. A modified kernel function includes the specific material parameters. Attention is given to the stability and accuracy of the numerical solution of the Hallen integral equation. The convergence and conditioning of the modified kernel function are studied and an upper error bound for the dipole current is derived. The antenna driving point impedance and efficiency are computed via the integral equation. The presented numerical examples demonstrate the strong dependence of the antenna properties on the used material and show the limits of nanoscale antennas.