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

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.

17pages, 4 figures, to be published in Physica C, Special Edition on Superconducting Pnictides, contains corrections to our previous paper PRL 101, 087004 (2008)

References in corpus (5)

• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• LaFeAsO${}_{1-x}$F${}_x$: A low carrier density superconductor near itinerant magnetism
• Competing Orders and Spin-Density-Wave Instability in La(O${}_{1-x}$F${}_x$)FeAs
• A possible ground state and its electronic structure of a mother material (LaOFeAs) of new superconductors

Cited by in corpus (1)

• Origin of Gap Anisotropy in Spin Fluctuation Models of the Fe-pnictides