Novel Magnetic Properties of Carbon Nanotubes

TL;DR

This paper predicts that external magnetic fields significantly alter the electronic properties of carbon nanotubes, inducing a metal-insulator transition and diverse magnetic responses, with findings consistent with experimental observations.

Contribution

It introduces the prediction of a field-induced metal-insulator transition and characterizes magnetic responses in carbon nanotubes, supported by universal scaling laws.

Findings

Magnetic field induces a metal-insulator transition in nanotubes.

Nanotubes show large diamagnetic and paramagnetic responses depending on conditions.

Universal scaling laws relate susceptibility to Fermi energy, temperature, and size.

Abstract

An external magnetic field is found to have strong effects on the electronic structure of carbon nanotubes. A field-induced metal-insulator transition is predicted for all pure nanotubes. In a weak field, nanotubes exhibit both large diamagnetic and paramagnetic responses which depend on the field direction, the position of the Fermi energy, the helicity, and the size of the nanotube. Universal scalings are found for the susceptibility as functions of the Fermi energy, the temperature, and the size of nanotubes. These results are in agreement with experiments.