Universality of electron correlations in conducting carbon nanotubes

TL;DR

This paper derives a universal low-energy Hamiltonian for interacting electrons in conducting carbon nanotubes, showing that their low-energy properties are largely independent of chirality, and investigates Mott-like instabilities with estimated energy gaps.

Contribution

It introduces a universal low-energy Hamiltonian for conducting nanotubes with arbitrary chirality, highlighting weak dependence on chiral angle and analyzing electron instabilities.

Findings

Low-energy properties are universal across different chiralities.

Energy gaps due to Mott-like instabilities are estimated between 0.01-0.1 eV.

Parameters show weak dependence on chiral angle.

Abstract

Effective low-energy Hamiltonian of interacting electrons in conducting single-wall carbon nanotubes with arbitrary chirality is derived from the microscopic lattice model. The parameters of the Hamiltonian show very weak dependence on the chiral angle, which makes the low energy properties of conducting chiral nanotubes universal. The strongest Mott-like electron instability at half filling is investigated within the self-consistent harmonic approximation. The energy gaps occur in all modes of elementary excitations and estimate at $0.01-0.1$ eV.