Band structure of superconducting Dirac electron systems

Abstract

The band structures of PbTe and SnTeare theoretically investigated. First- principles calculation is carried out on the basis of the density functional theory within the generalized gradient approximations. Then, in order to study the fine band structures in the low energy region, the tight-binding model is introduced based on the most localized Wannierfunctions derived from the first-principles calculations. It is found that the topology of the equal energy surface is different between PbTe and SnTe due to the spin-orbit interaction. The information of the topologically different Fermi surface will be important to study the superconducting mechanism on doped PbTeand SnTe.