Persistent Currents in Toroidal Single-wall Carbon Nanotubes

In this paper the persistent currents of ideal toroidal single-wall carbon nanotubes (TSWNTs) are calculated from the tight-binding model and the periodic boundary conditions. The electronic structure and persistent current of a TSWNT strongly depend on its helicity and longitudinalcircumference, making the TSWNTs a geometry-sensitive kind of materials. The interatomic carbonic interactions other than ppp-type are also studied and are found to introduce more steps to the persistent current. The diamagnetic-paramagnetic transitions occur more frequently, and the persistent current depends on the interaction energy values, while the periodicity of magnetic flux preserves.