Electronic specific heat of single-walled carbon nanotubes

The electronic structure of single-walled carbon nanotubes is calculated by the tight-binding model. A single-walled carbon nanotube could drastically change from a metal to a semiconductor or vice versa during the variation of magnetic flux. The low-temperature electronic specific heat thus exhibits the rich temperature and magnetic-flux dependence. There are four kinds of temperature dependence in the presence of the magnetic field, mainly due to the interaction between spin and magnetic field. Moreover, the magnetic-flux-dependent specific heat exhibits the pronounced oscillatory behavior including asymmetric two-peak structures. These structures strongly depend on the characteristics of the subbands nearest the Fermi level. © 1996 The American Physical Society.