Charge-transport and tunneling in single-walled carbon nanotubes

TL;DR

This paper experimentally studies charge transport in single-walled carbon nanotube bundles, revealing tunneling through contact barriers as the main conduction mechanism and quantifying how these barriers depend on temperature and bias current.

Contribution

It provides a quantitative model linking tunneling barriers to temperature and bias current in aligned nanotube bundles, advancing understanding of their transport properties.

Findings

Transport governed by tunneling between metallic regions.

Barrier amplitude depends on temperature and bias current.

Experimental data supports the tunneling model.

Abstract

We investigate experimentally the transport properties of single-walled carbon nanotube bundles as a function of temperature and applied current over broad intervals of these variables. The analysis is performed on arrays of nanotube bundles whose axes are aligned along the direction of the externally supplied bias current. The data are found consistent with a charge transport model governed by the tunnelling between metallic regions occurring through potential barriers generated by nanotubes contact areas or bundles surfaces. Based on this model and on experimental data we describe quantitatively the dependencies of the amplitude of these barriers upon bias current and temperature.