Ab initio spin‐dependent band structures of carbon nanotubes

Abstract

Using a linearized augmented cylindrical wave (LACW) approach taking into account the screw and rotational symmetries of carbon nanotubes (CNTs), the first principles technique for the spin‐dependent band structure calculations of single‐walled CNTs is developed. The method is applicable to any tubule independent on diameter and chirality. The calculations are based on the two‐component relativistic Hamiltonian and muffin‐tin and exchange approximations for potentials. As example, the band structures of the three chiral, one armchair, and one zigzag CNTs are calculated and presented as the functions of the screw wave vector and rotational quantum number. The spin‐orbit coupling effects appear as splitting of some nonrelativistic electron bands equal to between the 0.01 and 1 meV depending on the CNTs structure, rotational quantum number, and Brillouin zone position. In agreement with previous empirical tight‐binding theories, almost perfect polarization of spin is observed in the case of chiral tubules. © 2015 Wiley Periodicals, Inc.