Effect of Impurities with Internal Structure on Multiband Superconductors - Possible Enhancement of Transition Temperature -

Abstract

We study inelastic (dynamical) impurity scattering effects in two-band superconductors with the same ($s_{++}$ wave) or different ($s_{\pm }$ wave) sign order parameters. We focus on the enhancement of the superconducting transition temperature $T_{\mathrm{c}}$ by magnetic interband scattering with the interchange of crystal-field singlet ground and multiplet excited states. Either the $s_{++}$-wave or $s_{\pm }$-wave state is favored by the impurity-mediated pairing, which depends on the magnetic and nonmagnetic scattering strengths derived from the hybridization of the impurity states with the conduction bands. The details are examined for the singlet-triplet configuration that is suggestive of Pr impurities in the skutterudite superconductor LaOs${}_4$Sb${}_{12}$.

14 pages, 5 figures, to appear in J. Phys. Soc. Jpn. Vol. 79, No. 9 (2010)

References in corpus (17)

• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• Superconductivity at 22 K in Co-doped BaFe2As2 Crystals
• Magnetism, superconductivity, and pairing symmetry in Fe-based superconductors
• To What Extent Iron-Pnictide New Superconductors Have Been Clarified: A Progress Report
• Superconductivity in SrFe_(2-x)Co_xAs_2: Internal Doping of the Iron Arsenide Layers
• Band filling and interband scattering effects in MgB${}_2$: C vs Al doping
• NMR relaxation rate in superconducting pnictides: extended $s_{\pm }$ scenario
• Superfluid density of the $\pm$s-wave state for the iron-based superconductors
• Studies of Impurity-Doping Effects and NMR Measurement5s of La1111 and/or Nd 1111 Fe-Pnictide Superconductors
• Two types of s-wave pairing due to magnetic and orbital fluctuations in the two-dimensional 16-band d-p model for iron-based superconductors
• On the Superconductivity of LaFe1-yCoyAsO1-xFx
• Impurity Effects in Sign Reversing Fully-Gapped Superconductors: Analysis of FeAs Superconductors
• Impurity-induced in-gap state and Tc in sign-reversing s-wave superconductors: analysis of iron oxypnictide superconductors
• Intraband versus interband scattering rate effects in neutron irradiated MgB2
• Magnetic impurities in the two-band $s_{\pm }$-wave superconductors
• Eliashberg theory of superconductivity and inelastic rare-earth impurity scattering in filled skutterudite La${}_{1-x}$Pr${}_x$Os${}_4$Sb${}_{12}$
• Single Impurity Effects in Multiband Superconductors with Different Sign Order Parameters

Cited by in corpus (1)

• Effects of Impurities with Singlet-Triplet Configuration on Multiband Superconductors