Magnetization of armchair carbon tori

Magnetoelectronic states of armchair carbon tori are studied by the tight-binding model. They strongly depend on the magnitude and the direction of the magnetic field (B). B induces the destruction of state degeneracy, the change of energy spacing, and the semiconductor-metal transition (SMT). SMT's happen more frequently when B is relatively close to the toroid axis. Such characteristics are directly reflected in magnetic properties. Magnetization (M) exhibits special jump structures at $T=0$, mainly owing to SMT's. Magnitude of M and magnetism are mainly determined by the toroid radius $(R)$, the temperature, the angle (α) between the magnetic field and the symmetry axis, and the chirality. The dependence of M on radius (temperature) is strong at α=0^∘, but weak at α=90^∘. Most of armchair carbon tori are paramagnetic for α>30^∘. The critical angle in determining magnetism is αc30^∘. Armchair carbon tori quite differ from carbon tori near zigzag configuration (or armchair carbon nanotubes) in magnetoelectronic structures and magnetism.