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arXiv · 0808.3234

Theory for Superconductivity in Iron Pnictides at Large Coulomb U Limit

Wei-Qiang Chen·Kai-Yu Yang·Yi Zhou·Fu-Chun Zhang
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Abstract

Superconductivity in iron pnictides is studied by using a two-orbital Hubbard model in the large U limit. The Coulomb repulsion induces an orbital-dependent pairing between charge carriers. The pairing is found mainly from the scattering within the same Fermi pocket. The inter-pocket pair scatterings determine the symmetry of the superconductivity, which is extended s-wave at small Hund's coupling, and d-wave at large Hund's coupling and large U. The former is consistent with recent experiments of ARPES and Andreev reflection spectroscope.

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Wei-Qiang Chen, Kai-Yu Yang, Yi Zhou, Fu-Chun Zhang. 2008-12-18. Theory for Superconductivity in Iron Pnictides at Large Coulomb U Limit. https://doi.org/10.1103/physrevlett.102.047006

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