Non-Fermi liquid behavior in transport across carbon nanotube quantum dots

TL;DR

This paper develops a low-energy theoretical model for nonlinear transport in finite-size carbon nanotubes, revealing non-Fermi liquid behavior and predicting experimental features such as four-electron periodicity.

Contribution

It introduces a microscopic model combined with bosonization to explain nonlinear transport and degeneracy effects in carbon nanotube quantum dots.

Findings

Predicts four-electron periodicity in transport peaks

Shows degeneracy and coherence effects influence nonlinear conductance

Results align quantitatively with recent experimental data

Abstract

A low energy-theory for non-linear transport in finite-size single-wall carbon nanotubes, based on a microscopic model for the interacting pz electrons and successive bosonization, is presented. Due to the multiple degeneracy of the energy spectrum diagonal as well as off-diagonal (coherences) elements of the reduced density matrix contribute to the nonlinear transport. A four-electron periodicity with a characteristic ratio between adjacent peaks, as well as nonlinear transport features, in quantitative agreement with recent experiments, are predicted.