Conventional Superconductivity in Fe-Based Pnictides: the Relevance of Intra-Band Electron-Boson Scattering

Abstract

Various recent experimental data and especially the large Fe-isotope effect point against unconventional pairings, since the large intra-band impurity scattering is strongly pair-breaking for them. The strength of the inter-band impurity scattering in some single crystals may be strong and probably beyond the Born scattering limit. In that case the proposed s(+-) pairing (hole(h)- and electron(el)-gaps are of opposite signs) is suppressed but possibly not completely destroyed. The data imply that the intra-band pairing in the h- and in the el-band, which are inevitably due to some nonmagnetic el-boson interaction (EBI), must be taken into account. EBI is either due to phonons (EPI) or possibly due to excitons (EEI), or both are simultaneously operative. We discuss their interplay briefly. The large Fe-isotope effect favors the EPI and the s(+) pairing (the h- and el-gaps are in-phase).

7 pages, no figures, explanations and argumentations improved, references added

References in corpus (19)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• Is LaO${}_{1-x}$F${}_x$FeAs an electron-phonon superconductor ?
• Nearly Isotropic superconductivity in (Ba,K)Fe2As2
• Upper critical fields and thermally-activated transport of Nd(O_0.7F_0.3)FeAs single crystal
• The BCS-like gap in superconductor SmFeAsO_0.85F_0.15
• Multiband magnetism and superconductivity in Fe-based compounds
• ${}^{75}$As NMR studies of superconducting LaO${}_{0.9}$F${}_{0.1}$FeAs
• Microwave Penetration Depth and Quasiparticle Conductivity in PrFeAsO_1-y Single Crystals : Evidence for a Full-Gap Superconductor
• Spin-triplet p-wave pairing in a 3-orbital model for iron pnictide superconductors
• Field and Temperature Dependence of the Superfluid Density in LaO_{1-x}F_xFeAs Superconductors: A Muon Spin Relaxation Study
• Observation of Leggett's collective mode in a multi-band MgB2 superconductor
• Even Parity, Orbital Singlet and Spin Triplet Pairing for Superconducting $La(O_{1-x}{F}_x)FeAs$
• Growth and characterization of A_{1-x}K_xFe_2As_2 (A = Ba, Sr) single crystals with x=0 - 0.4
• A Generic Two-band Model for Unconventional Superconductivity and Spin-Density-Wave Order in Electron and Hole Doped Iron-Based Superconductors
• High-Field Pauli-Limiting Behavior and Strongly Enhanced Upper Critical Magnetic Fields near the Transition Temperature of an Arsenic-Deficient LaO_0.9F_0.1FeAs_(1-δ) Superconductor
• Interband superconductivity: contrasts between BCS and Eliashberg theory
• Impurity Effects in Sign Reversing Fully-Gapped Superconductors: Analysis of FeAs Superconductors
• Optical Study of LaO_0.9F_0.1FeAs: Evidence for a Weakly Coupled Superconducting State

Cited by in corpus (2)

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