Carbon nanotube antenna: Far-field, near-field and thermal-noise properties

A theory of the metallic achiral carbon nanotube (CNT) as a vibrator antenna is presented. The Leontovich-Levin integral equations method has been extended to the case of CNTs. Integral equations for the finite-length CNT and CNT bundles have been solved numerically in the integral operator quadrature approximation with the subsequent transition to the finite-order matrix equation. The radiation pattern, the antenna efficiency, the near-field spatial structure, the thermal noise have been evaluated and are analyzed. These characteristics of the CNT-based vibrators have been shown to be considerably different from the corresponding characteristics of their macroscopic analogues. The physical nature of this difference is dictated by the ability of metallic CNTs to support the strongly retarded weakly attenuated surface plasmons in THz and IR spectral ranges. Potentiality of CNTs as receiving and transmitting antennas for the THz range and as sources of directional coherent thermal emission are considered. (c) 2007 Elsevier B.V. All rights reserved.