Vibrational effects in the linear conductance of carbon nanotubes

TL;DR

This paper investigates how vibrational lattice fluctuations affect the linear conductance in single-wall carbon nanotubes, using density functional theory, molecular dynamics, and the Anderson model to analyze their impact on electron transport.

Contribution

It introduces a combined computational approach to quantify vibrational effects on conductance and proposes a simplified Anderson model to capture these effects qualitatively.

Findings

Structural fluctuations significantly influence conductance.

Frozen-phonon and molecular dynamics methods yield comparable results.

Vibrational modes and zero-point fluctuations impact electronic transport.

Abstract

We study the influence of structural lattice fluctuations on the elastic electron transport in single-wall carbon nanotubes within a density-functional-based scheme. In the linear response regime, the linear conductance is calculated via configurational averages over the distorted lattice. Results obtained from a frozen-phonon approach as well as from molecular dynamics simulations are compared. We further suggest that the effect of structural fluctuations can be qualitatively captured by the Anderson model with bond disorder. The influence of individual vibrational modes on the electronic transport is discussed as well as the role of zero-point fluctuations.