Theory for Superconductivity in Iron Pnictides at Large Coulomb U Limit

Abstract

Superconductivity in iron pnictides is studied by using a two-orbital Hubbard model in the large U limit. The Coulomb repulsion induces an orbital-dependent pairing between charge carriers. The pairing is found mainly from the scattering within the same Fermi pocket. The inter-pocket pair scatterings determine the symmetry of the superconductivity, which is extended s-wave at small Hund's coupling, and d-wave at large Hund's coupling and large U. The former is consistent with recent experiments of ARPES and Andreev reflection spectroscope.

4 pages, 4 figures, submit to prl

References in corpus (17)

• 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
• Superconductivity at 41 K and its competition with spin-density-wave instability in layered CeO${}_{1-x}$F${}_x$FeAs
• Spin density wave anomaly at 140 K in the ternary iron arsenide BaFe2As2
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
• Thorium-doping induced superconductivity up to 56 K in Gd1-xThxFeAsO
• Is LaO${}_{1-x}$F${}_x$FeAs an electron-phonon superconductor ?
• Superconductivity at 25 K in hole doped $(L{a}_{1-x}S{r}_x)OFeAs$
• Coexistence of the spin-density-wave and superconductivity in the (Ba,K)Fe2As2
• The BCS-like gap in superconductor SmFeAsO_0.85F_0.15
• Nodal Spin Density Wave and band topology of the FeAs based materials
• Proximity of antiferromagnetism and superconductivity in LaO${}_{1-x}$F${}_x$FeAs: effective Hamiltonian from ab initio studies
• Doping-dependent Phase Diagram of LaO{\it M}As ({\it M}=V--Cu) and Electron-type Superconductivity near Ferromagnetic Instability
• Iron-based layered superconductor LaO${}_{1-x}$F${}_x$FeAs: an antiferromagnetic semimetal
• Symmetry of superconducting states with two orbitals on a tetragonal lattice: application to $La{O}_{1-x}{F}_{x}FeAs$

Cited by in corpus (5)

• Pairing State with a time-reversal symmetry breaking in FeAs based superconductors
• Antiferromagnetically Driven Electronic Correlation in Iron Pnictides and Cuprates
• Antiferromagnetic Correlation and the Pairing Mechanism of the Cuprates and Iron Pnictides : a View From the Functional Renormalization Group Studies
• Band renormalization and Fermi surface reconstruction in iron-based superconductors
• Vortex state in iron-based superconductors with collinear antiferromagnetic cores