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arXiv · 0912.1811

Pairing mechanism in Fe pnictide superconductors

R. Chan·M. Gulacsi·A. Ormeci·A. R. Bishop
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Abstract

By applying an exact unitary transformation to a two-band hamiltonian which also includes the effects due to large pnictogen polarizabilities, we show that an attractive spin-mediated Hubbard term appears in the $d_{xz}$, $d_{yz}$ nearest-neighbour channel. This pairing mechanism implies a singlet superconducting order parameter in iron pnictides.

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R. Chan, M. Gulacsi, A. Ormeci, A. R. Bishop. 2009-12-09. Pairing mechanism in Fe pnictide superconductors. https://doi.org/10.1103/physrevb.82.132503

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