Magnetic Properties of Carbon Nanotubes

Abstract

Magnetic properties of carbon nanotubes (CN’s) are calculated in the effective-mass theory. The magnetic moment in a magnetic flux parallel to the tube axis oscillates as a function of the flux with period determined by the flux quantum and phase depending on whether CN is metallic or semiconducting. For a magnetic field perpendicular to the axis, CN’s exhibit a large diamagnetism independent of metallic or semiconducting. The magnetic moment induced by a perpendicular field is about three order of magnitude as large as that by a parallel field.