Unconventional pairing originating from disconnected Fermi surfaces in the iron-based superconductor
نویسندگان
چکیده
For the iron-based high Tc superconductor LaFeAsO1−xFx, we construct a minimal model, where all of the five Fe d bands turn out to be involved. We then investigate the origin of superconductivity with a five-band random-phase approximation by solving the Eliashberg equation. We conclude that the spin fluctuation modes arising from the nesting between the disconnected Fermi pockets realise, basically, an extended s-wave pairing, where the gap changes sign across the nesting vector.
منابع مشابه
Unconventional pairing originating from the disconnected Fermi surfaces of superconducting LaFeAsO1-xFx.
For a newly discovered iron-based high T_{c} superconductor LaFeAsO1-xFx, we have constructed a minimal model, where inclusion of all five Fe d bands is found to be necessary. The random-phase approximation is applied to the model to investigate the origin of superconductivity. We conclude that the multiple spin-fluctuation modes arising from the nesting across the disconnected Fermi surfaces r...
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