Electronic Properties of Armchair Carbon Nanotubes : Bosonization Approach

TL;DR

This paper derives a phase Hamiltonian for armchair carbon nanotubes considering long-range Coulomb interactions and uses renormalization group analysis to explore their low-energy properties, revealing a Mott insulator state at half-filling.

Contribution

It introduces a bosonization approach to derive the phase Hamiltonian for armchair nanotubes, clarifying differences from previous studies away from half-filling.

Findings

Ground state at half-filling is a Mott insulator with a spin gap.

Bound states of electrons form across sublattices.

Differences from previous results away from half-filling are explained.

Abstract

The phase Hamiltonian of armchair carbon nanotubes at half-filling and away from it is derived from the microscopic lattice model by taking the long range Coulomb interaction into account. We investigate the low energy properties of the system using the renormalization group method. At half-filling, the ground state is a Mott insulator with spin gap, in which the bound states of electrons at different atomic sublattices are formed. The difference from the recent results [Phys. Rev. Lett. 79, 5082 (1997)] away half-filling is clarified.