Robust $s_{\pm }$-wave superconductivity against multi-impurity in iron-based superconductors

Abstract

Effects of disorder on electron-doped iron pnictides are investigated systematically based on self-consistent Bogoliubov-de Gennes equations. Multiply impurities with same scattering potential (SP) are randomly distributed in a square lattice. Probability distribution functions of normalized order parameters for different impurity concentrations ${\delta }_{imp}$, different electron doping concentrations $\delta$ are investigated for given SPs. Samples are found to be very robust against weak SP, in which order parameters do not have qualitative change even at very large ${\delta }_{imp}$. While strong SP is able to easily break down the order parameters. For moderate SP, variations of order parameters on and around impurities strongly depend on $\delta$, however the distribution functions of normalized order parameters have similar behavior as ${\delta }_{imp}$ increases. Compared with superconducting (SC) order, the magnetic order is more sensitive to multi-impurity effect. The spatial spin density wave pattern has already been destroyed before the system loses its superconductivity. Dependence of SC order on temperature is similar to that of impurity-free case, with the critical temperature being remarkably suppressed for high ${\delta }_{imp}$.

7 pages, 8 figures

References in corpus (19)

• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• Magnetism, superconductivity, and pairing symmetry in Fe-based superconductors
• Determination of the phase diagram of the electron doped superconductor Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Funtional Renormalization Group Study of the Pairing Symmetry and Pairing Mechanism of the FeAs Based High Temperature Superconductors
• Electronic structure of the iron-based superconductor LaOFeP
• (pi,pi)-electronic order in iron arsenide superconductors
• NMR relaxation rate in superconducting pnictides: extended $s_{\pm }$ scenario
• Where Are the Extra d Electrons in Transition-Metal Substituted Fe Pnictides?
• Spin Fluctuations, Interband Coupling, and Unconventional Pairing in Iron-based Superconductors
• Superfluid density of the $\pm$s-wave state for the iron-based superconductors
• Momentum dependence and nodes of the superconducting gap in iron-pnictides
• Electronic structure of heavily electron-doped BaFe${}_{1.7}$Co${}_{0.3}$As${}_2$ studied by angle-resolved photoemission
• Superfluid density and penetration depth in Fe-pnictides
• Impurity-induced in-gap state and Tc in sign-reversing s-wave superconductors: analysis of iron oxypnictide superconductors
• Band renormalization and Fermi surface reconstruction in iron-based superconductors
• Quasiparticle states around a nonmagnetic impurity in electron-doped iron-based superconductors with spin-density-wave order
• Insensitivity of superconductivity to disorder in the cuprates
• Domain Walls in Normal and Superconducting States of Iron Pnictides