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Related papers: Effects of impurities on Hc2(T) in superconductors…

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We investigate the upper critical field in a dirty two-band superconductor within quasiclassical Usadel equations. The regime of very high anisotropy in the quasi-2D band, relevant for MgB$_{2}$, is considered. We show that strong…

Superconductivity · Physics 2009-11-10 A. A. Golubov , A. E. Koshelev

The impurity concentration dependence of superconducting transition temperature $T_c$ is studied within the framework of two band model of order parameter anisotropy. Both intraband and interband electron scattering by nonmagnetic and…

Superconductivity · Physics 2007-05-23 P. I. Arseev , N. K. Fedorov , S. O. Loiko

We calculate the singlet-triplet splitting for a couple of two-dimensional electrons in the potential of two positively charged impurities which are located out of plane. We consider different relations between vertical distances of…

Strongly Correlated Electrons · Physics 2009-10-31 I. V. Ponomarev , V. V. Flambaum , A. L. Efros

I calculated the effect of magnetic impurities on the normal and superconductive properties of a multiband s-wave superconductor by direct solution of the two-band Eliashberg equations. In this way I determined the critical temperature, the…

Superconductivity · Physics 2007-05-23 G. A. Ummarino

The impurity effects are studied for the BiS_{2}- layered superconductors based on a two orbital model with the Bogoliubov-de-Gennes technique. The superconducting critical temperature (T_{c}) as a function of the mpurity concentration is…

Superconductivity · Physics 2013-10-29 S. L. Liu

Angle-resolved upper critical field $H_{c2}$ provides an efficient tool to probe the gap symmetry of unconventional superconductors. We revisit the behavior of in-plane $H_{c2}$ in $d$-wave superconductors by considering both the orbital…

Superconductivity · Physics 2016-07-05 Jing-Rong Wang , Guo-Zhu Liu , Chang-Jin Zhang

From the magnetic response of Nb-cylinders to time-varying fields the AC-conductivity, $\sigma'-i\sigma''$, and the critical current density $J_c^s$ are determined above the upper critical field $H_{c2}$. The field dependencies of $\sigma'$…

Superconductivity · Physics 2007-05-23 Sara Casalbuoni , Lars von Sawilski , Jürgen Kötzler

Despite the intense activity in the year since the discovery of superconductivity in MgB2, key parameters, in particular the upper and lower critical fields Hc2 and Hc1 and their anisotropies, are not well-established, largely because of…

Superconductivity · Physics 2009-11-07 G. K. Perkins , J. Moore , Y. Bugoslavsky , L. F. Cohen , J. Jun , S. M. Kazakov , J. Karpinski , A. D. Caplin

We study the influence of spin exchange interaction of impurity scattering on critical temperature of anisotropic impure superconductors. The model of random nonmagnetic and magnetic impurity are revised to cover the effect of spin exchange…

Superconductivity · Physics 2009-11-13 P. Udomsamuthirun , R. Supadanaison

Strong coupling effects on the upper critical fields $H_{c2}$ along the c-axis in the noncentrosymmetric heavy fermion superconductors near quantum criticality CeRhSi$_3$ and CeIrSi$_3$ are examined. For sufficiently large spin-orbit…

Strongly Correlated Electrons · Physics 2009-11-13 Y. Tada , N. Kawakami , S. Fujimoto

We study the spatial behaviour of coherency and magnetic field in a two-orbital superconductor. The superconducting phase transition is caused here by the on-site intra-orbital attractions (negative-U Hubbard model) and inter-orbital…

Superconductivity · Physics 2012-11-26 G. Litak , T. Örd , K. Rägo , A. Vargunin

Magnetic properties of dirty multiband superconductors near the upper critical field are studied. The parameter $\kappa_2$ characterizing magnetization slope is shown to have a significant temperature variation which is quite sensitive to…

Superconductivity · Physics 2016-06-22 Mikhail Silaev

We consider magnetic impurities in a two dimensional superfluid Fermi gas in the presence of spin-orbit coupling. By using the methods of t-matrix and Green's function, we find spin-orbit coupling has some dramatic impacts on the effects of…

Quantum Gases · Physics 2013-01-07 Zhongbo Yan , Xiaosen Yang , Liang Sun , Shaolong Wan

Although their crystal structures are complex, all high temperature superconductors contain some crystal planes consisting of only Cu and O atoms in a square lattice. Superconductivity is believed to originate from strongly interacting…

Superconductivity · Physics 2009-10-31 S. H. Pan , E. W. Hudson , K. M. Lang , H. Eisaki , S. Uchida , J. C. Davis

The pseudogap phenomena in the cuprate superconductors requires a theory beyond the mean field BCS level. A natural candidate is to include strong pairing fluctuations, and treat the two-particle and single particle Green's functions…

Superconductivity · Physics 2007-05-23 Qijin Chen , J. R. Schrieffer

The pointlike impurity scattering is studied for a superconductor with different pairing symmetries based on a minimal two band model proposed by S. Raghu $et$ $al.$ [Phys. Rev. B {\bf 77}, R220503 (2008)], and the self-consistent…

Superconductivity · Physics 2009-11-10 Tao Zhou , Xiang Hu , Jian-Xin Zhu , C. S. Ting

We calculate the anomalous Hall conductance of superconductors with spin-orbit interaction and with either uniform or local magnetization. In the first case we consider a uniform ferromagnetic ordering in a spin triplet superconductor,…

Superconductivity · Physics 2015-06-03 P. D. Sacramento , M. A. N. Araujo , V. R. Vieira , V. K. Dugaev , J. Barnas

The paramagnetic spin-triplet superconductor UTe$_2$ has attracted significant attention because of its exotic superconducting properties including an extremely high upper critical field and possible chiral superconducting states. Recently,…

We compare the effects of in-plane non magnetic Li$^{+}$ and Zn$^{2+}$ impurities on the normal state of high-T$_{c}$ cuprates. Y NMR shows that the extra hole introduced by Li is not localized in its vicinity. The Tc depression and induced…

Superconductivity · Physics 2009-10-31 J. Bobroff , W. A. MacFarlane , H. Alloul , P. Mendels , N. Blanchard , G. Collin , J. -F. Marucco

This paper presents a brief review on the reported anisotropic properties of MgB2, in the superconducting state (e.g. upper critical field Hc2, field penetration depth, coherence length, energy gap) as well as in the normal state (e.g.,…

Superconductivity · Physics 2007-05-23 O. F. de Lima