Nontrivial effects of point-like disorder on critical fields and pinning in s<sub>±</sub> superconductors

ORAL

Abstract

In most superconductors non-magnetic point-like defects enhance pinning and upper critical field. However, in s± superconductors, for example iron-based compounds, point-like disorder influences not only intra-band potential scattering, but also inter-band pair-breaking scattering rates. The latter leads to suppression of Tc, Hc2 and the condensation energy. The balance between these opposite effects leads to an increase of (dHc2/dT)T=Tc slope with the decrease of Tc, opposite to what is observed as a function of doping. Even more unusual, it may also lead to a suppression of strong pinning believed to be responsible for a sharp peak in magnetization near H=0. In our experiments controlled disorder was induced by 2.5 MeV electron irradiation.

*This work was supported by the US DOE, Office of Science, BES Materials Science and Engineering Division under contract #DE-AC02-07CH11358.

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Presenters

  • Ruslan Prozorov

    • Ames Laboratory US DOE, Ames, Iowa
    • Iowa State University
    • Ames Laboratory, Iowa State University
    • Ames Laboratory
    • Ames Laboratory and Iowa state University, USA
    • Ames Laboratory and Iowa State University, Ames, IA, USA
    • Ames Laboratory and Department of Physics & Astronomy, Iowa State University, Ames, IA 50010, USA

Authors

  • Ruslan Prozorov

    • Ames Laboratory US DOE, Ames, Iowa
    • Iowa State University
    • Ames Laboratory, Iowa State University
    • Ames Laboratory
    • Ames Laboratory and Iowa state University, USA
    • Ames Laboratory and Iowa State University, Ames, IA, USA
    • Ames Laboratory and Department of Physics & Astronomy, Iowa State University, Ames, IA 50010, USA

  • Marcin Konczykowski

    • Laboratoire des Solides Irradiés, École Polytechnique, F-91128 Palaiseau, France
    • Ecole Polytechnique
    • Ecole Polytechnique, Palaiseau, France
    • LSI, Ecole Polytechnique
    • Laboratoire des Solides Irradies, Ecole Polytechnique

  • Vladimir G. Kogan

    • Ames Laboratory, Iowa State University
    • Ames Laboratory

  • Makariy Tanatar

    • Ames Laboratory
    • Ames Laboratory US DOE, Ames, Iowa
    • Ames Laboratory and Iowa State University, Ames, IA, USA
    • Ames Laboratory and Department of Physics & Astronomy, Iowa State University, Ames, IA 50010, USA