Evolution of superconductivity in SrFe$_2$As$_2$ with Ni and Pt substitution

ORAL

Abstract

The superconducting state in the iron pnictide compounds with tetragonal ThCr$_2$Si$_2$ crystal structure has attracted much interest. Transition metal substitution is known to suppress the antiferromagnetic phase of the parent compounds, yielding superconductivity with maximum $T_c$ values approaching $\sim$20-25~K when Co, Ni, Ru, Rh, Pd, or Ir are used to replace Fe. However, this trend is known to be broken in the case of SrFe$_{2-x}$Ni$_x$As$_2$ and SrFe$_{2-x}$Pd$_x$As$_2$, which both exhibit reduced maximum $T_c$ values of order 10~K. We will present the effects of Ni and Pt substitution in single crystalline SrFe$_2$As$_2$ as measured by resistivity, magnetic susceptibility and specific heat, and discuss how our results relate to the isoelectronic case of Pd substitution as well as other neighboring transition metal substitution series.

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Authors

  • S. Saha

    • University of Maryland, Physics Department
    • University of Maryland, College Park
    • Center for Nanophysics and Advanced Materials, University of Maryland
    • Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD 20742
    • Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland
    • University of Maryland, College Park, Center for Nanophysics and Advanced Materials

  • T. Drye

    • Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland

  • K. Kirshenbaum

    • University of Maryland, Physics Department
    • Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA
    • Center for Nanophysics and Advanced Materials, University of Maryland
    • Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD 20742
    • Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland
    • University of Maryland, College Park, Center for Nanophysics and Advanced Materials

  • Nicholas Butch

    • University of Maryland, Physics Department
    • University of Maryland, College Park
    • UC San Diego
    • Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD 20742
    • Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA
    • Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland
    • University of Maryland

  • Xiaohang Zhang

    • University of Maryland, Physics Department
    • Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland
    • Center for Nanophysics and Advanced Materials, University of Maryland, College Park

  • R. Greene

    • Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland

  • J. Paglione

    • University of Maryland, College Park
    • University of Maryland
    • Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA
    • Center for Nanophysics and Advanced Materials, University of Maryland
    • Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD 20742
    • Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland
    • University of Maryland, College Park, Center for Nanophysics and Advanced Materials