J. Phys. Soc. Jpn. 77 (2008) Supplement C pp. 96-98  |Previous Article| |Next Article|  |Table of Contents|
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Proc. Int. Symp. Fe-Pnictide Superconductors

Unconventional Superconductivity Originating from Disconnected Fermi Surfaces in the Iron-Based Oxypnictide

Kazuhiko Kuroki¹, Seiichiro Onari², Ryotaro Arita³, Hidetomo Usui¹, Yukio Tanaka², Hiroshi Kontani⁴, and Hideo Aoki⁵

(Received August 4, 2008)

For a newly discovered iron-based high T_c superconductor LaFeAsO_1-xF_x, we have first constructed 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 across the disconnected Fermi pockets realize an extended s-wave pairing, where, to be precise, the gap function is a 5×5 matrix.

URL: http://jpsj.ipap.jp/link?JPSJS/77SC/96/

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