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arXiv · 0902.3691

Unconventional pairing originating from disconnected Fermi surfaces in the iron-based superconductor

Kazuhiko Kuroki·Hideo Aoki
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Abstract

For the iron-based high $T_c$ superconductor LaFeAsO$_{1-x}$F$_x$, 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.

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Kazuhiko Kuroki, Hideo Aoki. 2009-02-21. Unconventional pairing originating from disconnected Fermi surfaces in the iron-based superconductor. https://doi.org/10.1088/1367-2630%2F11%2F2%2F025017

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