Electron–phonon induced conductance gaps in carbon nanotubes

This work presents a theoretical study of quantum charge transport through zigzag and armchair carbon nanotubes in the presence of electron–phonon interaction. By using a non-perturbative description of the electron–phonon coupling in Fock space, one reveals the occurrence of a transmission gap opening at half the optical A1(L) phonon energy, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$\hbar\omega_{0}/2$\end{document}, above (below) the charge neutrality point associated with phonon emission (absorption). This mechanism, which is prevented at low bias voltages by Pauli blocking, develops when the system is driven out of equilibrium (high bias voltages). This yields an onset of current saturation of about 30 μA, which brings a completely novel perspective to understand electrical characteristics of nanotube-based devices.