Phonon-assisted tunneling in interacting suspended single wall carbon nanotubes

TL;DR

This paper investigates how electron-phonon interactions influence electronic transport in suspended metallic single wall carbon nanotubes with strong electron-electron interactions, revealing distinct phonon-assisted conductance features.

Contribution

It models the coupled electron-phonon system in finite-length nanotubes using the Luttinger liquid framework, highlighting the impact on conductance spectra.

Findings

Differential conductance shows three families of peaks due to spectrum discreteness.

Phonon-assisted peaks are highly sensitive to system parameters.

Peaks are most prominent near the Wentzel-Bardeen singularity.

Abstract

Transport in suspended metallic single wall carbon nanotubes in the presence of strong electron-electron interaction is investigated. We consider a tube of finite length and discuss the effects of the coupling of the electrons to the deformation potential associated to the acoustic stretching and breathing modes. Treating the interacting electrons within the framework of the Luttinger liquid model, the low-energy spectrum of the coupled electron-phonon system is evaluated. The discreteness of the spectrum is reflected in the differential conductance which, as a function of the applied bias voltage, exhibits three distinct families of peaks. The height of the phonon-assisted peaks is very sensitive to the parameters. The phonon peaks are best observed when the system is close to the Wentzel-Bardeen singularity.