Phonon runaway in nanotube quantum dots

TL;DR

This paper investigates how strong electron-phonon interactions in nanotube quantum dots lead to hot phonon effects, explaining anomalous conductance features observed experimentally.

Contribution

It introduces a rate equation approach for electron-phonon correlations, revealing the significance of hot phonons in transport phenomena beyond traditional models.

Findings

Observation of hot phonon effects in SWCNT quantum dots

Quantitative explanation of anomalous conductance signatures

Evidence of strong electron-phonon coupling

Abstract

We explore electronic transport in a nanotube quantum dot strongly coupled with vibrations and weakly with leads and the thermal environment. We show that the recent observation of anomalous conductance signatures in single-walled carbon nanotube (SWCNT) quantum dots can be understood quantitatively in terms of current driven `hot phonons' that are strongly correlated with electrons. Using rate equations in the many-body configuration space for the joint electron-phonon distribution, we argue that the variations are indicative of strong electron-phonon coupling requiring an analysis beyond the traditional uncorrelated phonon-assisted transport (Tien-Gordon) approach.