MDPIActa Medica Okayama2073-89941212020Relation of Superconducting Pairing Symmetry and Non-Magnetic Impurity Effects in Vortex States175ENYasuakiSeraDepartment of Physics, Okayama UniversityTakahiroUedaDepartment of Physics, Okayama UniversityHirotoAdachiDepartment of Physics, Okayama UniversityMasanoriIchiokaDepartment of Physics, Okayama UniversityNon-magnetic impurity scattering effects on the vortex core states are theoretically studied to clarify the contributions from the sign-change of the pairing function in anisotropic superconductors. The vortex states are calculated by the Eilenberger theory in superconductors with px-wave pairing symmetry, as well as the corresponding anisotropic s-wave symmetry. From the spatial structure of the pair potential and the local electronic states around a vortex, we examine the differences between anisotropic superconductors with and without sign-change of the pairing function, and estimate how twofold symmetric vortex core images change with increasing the impurity scattering rate both in the Born and the unitary limits. We found that twofold symmetric vortex core image of zero-energy local density of states changes the orientation of the twofold symmetry with increasing the scattering rate when the sign change occurs in the pairing function. Without the sign change, the vortex core shape reduces to circular one with approaching dirty cases. These results of the impurity effects are valuable for identifying the pairing symmetry by observation of the vortex core image by the STM observation.No potential conflict of interest relevant to this article was reported.Acta Medica Okayama72222005Electronic structure and spontaneous internal field around nonmagnetic impurities in spin-triplet chiral p-wave superconductorsENMitsuakiTakigawaMasanoriIchiokaKazuhikoKurokiYukioTanaka<p>The electronic structure around an impurity in spin-triplet p-wave superconductors is studied by the Bogoliubov-de Gennes theory on a tight-binding model, where we have chosen sin p(x)+i sin p(y)-wave or sin(p(x)+p(y))+i sin(-p(x)+p(y))-wave states, which are considered to be candidates for the pairing state in Sr2RuO4. We calculate the spontaneous current and the local density of states around the impurity and discuss the difference between the two types of pairing. We propose that it is possible to discriminate the two pairing states by studying the spatial dependence of the magnetic field around a pair of impurities.</p>No potential conflict of interest relevant to this article was reported.American Physical Society (APS)Acta Medica Okayama2469-9950105102022Antiferromagnetic spin Seebeck effect across the spin-flop transition: A stochastic Ginzburg-Landau simulation104417-1104417-14ENYutakaYamamotoDepartment of Physics, Okayama UniversityMasanoriIchiokaResearch Institute for Interdisciplinary Science, Okayama UniversityHirotoAdachiResearch Institute for Interdisciplinary Science, Okayama UniversityWe investigate the antiferromagnetic spin Seebeck effect across the spin-flop transition in a numerical simulation based on the time-dependent Ginzburg-Landau equation for a bilayer of a uniaxial insulating antiferromagnet and an adjacent metal. By directly simulating the rate of change of the conduction-electron spin density s in the adjacent metal layer, we demonstrate that a sign reversal of the antiferromagnetic spin Seebeck effect across the spin-flop transition occurs when the interfacial coupling of s to the staggered magnetization n of the antiferromagnet dominates, whereas no sign reversal appears when the interfacial coupling of s to the magnetization m dominates. Moreover, we show that the sign reversal is influenced by the degree of spin dephasing in the metal layer. Our result indicates that the sign reversal is not a generic property of a simple uniaxial antiferromagnet, but controlled by microscopic details of the exchange coupling at the interface and the spin dephasing in the metal layer.No potential conflict of interest relevant to this article was reported.