Magnetic response of chiral carbon nanotori: The dependence of torus radius

Based on tight-binding approximation, the magnetic moments of chiral “metallic” carbon nanotori (i.e., nanotori formed from metallic carbon nanotubes) are investigated by application of London theory. It is shown that in the vicinity of zero magnetic field, a chiral “metallic” carbon nanotorus (n,m,p=3I)(n,m,p=3I) would exhibit diamagnetic response, while paramagnetic response for these “metallic” carbon nanotorus (n,m,p≠3I)(n,m,p≠3I), with I an integer. This prediction differs from previous conclusions, which can be ascribed to curvature effect considered in our calculation.