Analysis of Multiwalled Carbon Nanotubes as Waveguides and Antennas in the Infrared and the Visible Regimes

TL;DR

This paper theoretically investigates the waveguiding and antenna properties of multiwalled carbon nanotubes across infrared and visible frequencies, highlighting their potential and limitations due to material effects.

Contribution

It provides a comprehensive theoretical analysis of guided wave propagation and antenna resonances in MWCNTs, including effects of interband transitions and core materials.

Findings

Guided waves are slightly attenuated in mid-infrared regimes.

Interband transitions impair guided wave propagation and antenna performance.

Surface-plasmon waves are suppressed in the visible regime due to lossy shells.

Abstract

The propagation of azimuthally symmetric guided waves in multiwalled carbon nanotubes (MWCNTs) was analyzed theoretically in the mid-infrared and the visible regimes. The MWCNTs were modeled as ensembles of concentric, cylindrical, conducting shells. Slightly attenuated guided waves and antenna resonances due to the edge effect exist for not-too-thick MWCNTs in the far- and mid-infrared regimes. Interband transitions hinder the propagation of guided waves and have a deleterious effect on the performance of a finite-length MWCNT as an antenna. Propagation of surface-plasmon waves along an MWCNT with a gold core was also analyzed. In the near-infrared and the visible regimes, the shells behave effectively as lossy dielectrics suppressing surface-plasmon-wave propagation along the gold core.