Topological Metal of NaBi with Ultralow Lattice Thermal Conductivity and   Electron-phonon Superconductivity
  By means of first-principles and \emph{ab initio} tight-binding calculations, we found that the compound of NaBi is a three-dimensional non-trivial topological metal. Its topological feature can be confirmed by the presence of band inversion, the derived effective Z$_2$ invariant and the non-trivial surface states with the presence of Dirac cones. Interestingly, our calculations further demonstrated that NaBi exhibits the uniquely combined properties between the electron-phonon coupling superconductivity in nice agreement with recent experimental measurements and the obviously anisotropic but extremely low thermal conductivity. The spin-orbit coupling effects greatly affect those properties. NaBi may provide a rich platform to study the relationship among metal, topology, superconductivity and thermal conductivity. 
Xing-Qiu Chen, Ronghan Li, Yan Sun, Xiyue Cheng, Dianzhong Li, Yiyi Li
cond-mat.mtrl-sci