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.

–

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