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arXiv · 0803.2740

Unconventional sign-reversing superconductivity in LaFeAsO_(1-x)F_x

I. I. Mazin·D. J. Singh·M. D. Johannes·M. H. Du
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Abstract

We argue that the newly discovered superconductivity in a nearly magnetic, Fe-based layered compound is unconventional and mediated by antiferromagnetic spin fluctuations, though different from the usual superexchange and specific to this compound. This resulting state is an example of extended s-wave pairing with a sign reversal of the order parameter between different Fermi surface sheets. The main role of doping in this scenario is to lower the density of states and suppress the pair-breaking ferromagnetic fluctuations.

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I. I. Mazin, D. J. Singh, M. D. Johannes, M. H. Du. 2008-08-07. Unconventional sign-reversing superconductivity in LaFeAsO_(1-x)F_x. https://doi.org/10.1103/physrevlett.101.057003

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