Orbital upper critical field of type-II superconductors with pair breaking

TitleOrbital upper critical field of type-II superconductors with pair breaking
Publication TypeJournal Article
Year of Publication2013
AuthorsKogan VG, Prozorov R
Journal TitlePhysical Review B
Volume88
Pages024503
Date Published07
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberWOS:000321669300013
Keywordscoherence length, critical-temperature, dependence, impurities
Abstract

The orbital upper critical field H-c2 is evaluated for isotropic materials with arbitrary transport and pair-breaking scattering rates. It is shown that unlike transport scattering which enhances H-c2, the pair breaking suppresses the upper critical field and reduces the dimensionless ratio h*(0) = H-c2(0)/T-c (dH(c2)/dT)(Tc) from the Helfand-Werthamer value of approximate to 0.7 to 0.5 for a strong pair breaking. h*(T) is evaluated for arbitrary transport and pair-breaking scattering. A phenomenological model for the pair-breaking suppression by magnetic fields is introduced. It shows qualitative features such as a positive curvature of H-c2(T) and the low temperature upturn usually associated with multiband superconductivity.

URL<Go to ISI>://WOS:000321669300013
DOI10.1103/PhysRevB.88.024503