Encapsulated Nanowires: Boosting Electronic Transport in Carbon Nanotubes

TL;DR

Encapsulating atomic chains within carbon nanotubes enhances phonon decay, significantly reducing electrical resistivity and boosting electronic transport by providing additional thermalisation pathways.

Contribution

This work introduces a novel method of encapsulating atomic chains in CNTs to improve phonon decay and electrical conductivity, based on first-principles calculations.

Findings

Encapsulation reduces resistivity by 51% in tested systems.

Enhanced phonon decay channels improve electronic transport.

Encapsulation strategy can be applied to optimize CNT-based devices.

Abstract

The electrical conductivity of metallic carbon nanotubes (CNTs) quickly saturates with respect to bias voltage due to scattering from a large population of optical phonons. Decay of these dominant scatterers in pristine CNTs is too slow to offset an increased generation rate at high voltage bias. We demonstrate from first principles that encapsulation of 1D atomic chains within a single-walled CNT can enhance decay of "hot" phonons by providing additional channels for thermalisation. Pacification of the phonon population growth reduces electrical resistivity of metallic CNTs by 51% for an example system with encapsulated beryllium.