Universal Features of Quantized Thermal Conductance of Carbon Nanotubes

TL;DR

This paper reveals universal quantized thermal conductance features in carbon nanotubes, showing independence from size or structure at low temperatures and including electronic contributions in metallic CNTs, based on theoretical analysis.

Contribution

It provides a theoretical demonstration of universal quantization in thermal conductance of CNTs, highlighting the role of phonons and electrons across different types.

Findings

Phonon thermal conductance of semiconducting CNTs is universally quantized at low temperatures.

Metallic CNTs show additional quantized electronic contributions to thermal conductance.

Thermal conductance follows a universal temperature scaling law.

Abstract

The universal features of quantized thermal conductance of carbon nanotubes (CNTs) are revealed through theoretical analysis based on the Landauer theory of heat transport. The phonon-derived thermal conductance of semiconducting CNTs exhibits a universal quantization in the low temperature limit, independent of the radius or atomic geometry. The temperature dependence follows a single curve given in terms of temperature scaled by the phonon energy gap. The thermal conductance of metallic CNTs has an additional contribution from electronic states, which also exhibits quantized behavior up to room temperature.