Single-orbital realization of high-temperature s± superconductivity in the square-octagon lattice

  title={Single-orbital realization of high-temperature 
 superconductivity in the square-octagon lattice},
  author={Yao-Tai Kang and Chen Lu and Fan Yang and Dao-Xin Yao},
  journal={Physical Review B},
The remarkable $s\pm$ superconductivity (SC) is well known in the iron-based superconductors, which are of multi-orbital characteristic. Here we propose a single-orbital realization of this intriguing pairing state with high superconducting critical temperature $T_c$ in the square-octagon lattice, which is hosted by a few real materials. Owing to the perfect Fermi surface nesting at half-filling, arbitrarily weak Hubbard-interaction drives long-range spin-density wave (SDW) with Neel… 
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