Conductance of Distorted Carbon Nanotubes

TL;DR

This paper investigates how structural distortions, specifically bending, affect the electrical transport properties of armchair carbon nanotubes, revealing increased resistance and localized states due to curvature-induced hybridization.

Contribution

It provides a detailed analysis of how bending influences conductance and identifies the role of localized states and hybridization in transport properties.

Findings

Bending decreases transmission function in certain energy ranges.

Localized states with $\sigma$-$\pi$ hybridization are induced by curvature.

Large contact resistances are due to weak coupling in side bonded configurations.

Abstract

We have calculated the effects of structural distortions of armchair carbon nanotubes on their electrical transport properties. We found that the bending of the nanotubes decreases their transmission function in certain energy ranges and leads to an increased electrical resistance. Electronic structure calculations show that these energy ranges contain localized states with significant $\sigma$-$\pi$ hybridization resulting from the increased curvature produced by bending. Our calculations of the contact resistance show that the large contact resistances observed for SWNTs are likely due to the weak coupling of the NT to the metal in side bonded NT-metal configurations.