Fundamental transmitting properties of carbon nanotube antennas

P.J. Burke et al. (see http://xxx.lanl.gov/abs/cond-mat/0408418) considered carbon nanotube dipole antennas based on a transmission-line model. This paper investigates fundamental properties of dipole antennas formed by carbon nanotubes using a Halle´n´s-type integral equation. The input impedance, radiation pattern, and current profiles are presented and compared to those of ordinary metallic antennas of the same size and shape. Possible applications of carbon nanotube antennas are discussed. The carbon nanotube is accounted for using a semi-classical conductivity derived explicitly for infinite carbon nanotubes (Maksimenko, S.A. et al., Phys. Rev. B, vol.60, p.17136-49, 1999). At the frequencies of interest, this semi-classical conductivity is equivalent to the more rigorous (and complicated) quantum mechanical conductivity also derived by Maksimenko et al. Thus, the integral equation method utilized can be considered as a semi-classical technique, since the quantum-mechanical nature of the CN conductivity is accounted for, yet the classical Maxwell´s equations are used. This formulation should be accurate through THz frequencies.