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

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 نشر من قبل Michelle Johannes
 تاريخ النشر 2008
  مجال البحث فيزياء
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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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