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arXiv · 1211.5435

Pairing Symmetry in Layered BiS$_2$ Compounds Driven by Electron-Electron Correlation

Yi Liang·Xianxin Wu·Wei-Feng Tsai·Jiangping Hu
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Abstract

We investigate the pairing symmetry of layered BiS$_2$ compounds by assuming that electron-electron correlation is still important so that the pairing is rather short range. We find that the extended s-wave pairing symmetry always wins over d-wave when the pairing is confined between two short range sites up to next nearest neighbors. The pairing strength is peaked around the doping level x=0.5, which is consistent with experimental observation. The extended s-wave pairing symmetry is very robust against spin-orbital coupling because it is mainly determined by the structure of Fermi surfaces. Moreover, the extended s-wave pairing can be distinguished from conventional s-wave pairing by measuring and comparing superconducting gaps of different Fermi surfaces.

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Yi Liang, Xianxin Wu, Wei-Feng Tsai, Jiangping Hu. 2014-04-17. Pairing Symmetry in Layered BiS$_2$ Compounds Driven by Electron-Electron Correlation. https://doi.org/10.1007/s11467-013-0407-8

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