Optical properties of coiled carbon nanotubes: A simple model

Abstract

Experimental evidence of regularly coiled carbon nanotubes have been reported in 1994. They are predicted to have excellent electro-magnetic properties, although their structure, formation mechanism and theoretical aspects are still subjects of scientific discussions. We propose model of hexagonal, helically coiled single wall carbon nanotubes, and determine their line group symmetry. Further, we calculate electronic band structure and optical conductivity of the various configurations of coiled nanotubes by means of fully symmetry adopted density functional tight binding implemented into the POLSym code. Comparison of conducting and optical properties of coiled and straight armchair carbon nanotubes is shown. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.