Ab initio study of transport properties in defected carbon nanotubes: an O(N) approach

TL;DR

This paper combines ab initio simulations with linear-scaling Green's functions to analyze how realistic defects affect the electronic transport in long carbon nanotubes, providing insights into their conductance and localization length.

Contribution

It introduces an efficient O(N) approach integrating ab initio methods with Green's functions to study defect effects on transport in long carbon nanotubes.

Findings

Defects significantly influence nanotube conductance.

Localization length varies with defect type and tube diameter.

Method enables statistical analysis of large defected nanotube samples.

Abstract

A combination of ab initio simulations and linear-scaling Green's functions techniques is used to analyze the transport properties of long (up to one micron) carbon nanotubes with realistic disorder. The energetics and the influence of single defects (mono- and di-vacancies) on the electronic and transport properties of single-walled armchair carbon nanotubes are analyzed as a function of the tube diameter by means of the local orbital first-principles Fireball code. Efficient O(N) Green's functions techniques framed within the Landauer-Buttiker formalism allow a statistical study of the nanotube conductance averaged over a large sample of defected tubes and thus extraction of the nanotubes localization length. Both the cases of zero and room temperature are addressed.