Zr$_{5}$Sb$_{3}$-first Superconductor in the Mn$_{5}$Si$_{3}$-type system

POSTER

Abstract

Systematic exploration for superconductivity in the Zr$_{5}$X$_{3}$ (x$=$Sb, Sn, Ge, Ga, and Al) system have been carried out, and we report the discovery of superconductivity at 2.3 K in Zr$_{5}$Sb$_{3}$, the first superconducting member in the large compound family of the Mn$_{5}$Si$_{3}$-structure type. Transport, magnetic, and calorimetric measurements clearly demonstrate the bulk superconductivity for the Zr$_{5}$Sb$_{3}$ and band structure calculations suggest it to be a possible phonon-mediated BCS superconductor, with a relatively large density of states at the Fermi level associated with the d-electrons of Zr and substantially larger electron-phonon coupling compared to the Sn counterpart compound Zr$_{5}$Sn$_{3}$. Detailed doping studies have shown that superconductivity in Zr$_{5}$Sb$_{3}$ is rather robust with Hf- and Y-substitution of Zr, but suppressed by Ti-substitution. It is also suppressed by interstitial filling in Zr$_{5}$Sb$_{3}$Z by Z $=$ Sb, C, or O.

Authors

  • Bing Lv

    • Department of Physics and the Texas Center for Superconductivity, University of Houston
    • TcSUH and Dept. of Physics, University of Houston
    • Texas Center for Superconductivity, University of Houston

  • X.Y. Zhu

    • TcSUH and Dept. of Physics, University of Houston

  • Bernd Lorenz

    • TCSUH and Dept. of Physics, University of Houston
    • TcSUH and Dept. of Physics, University of Houston
    • Department of Physics and TcSUH

  • F.Y. Wei

    • TcSUH and Dept. of Physics, University of Houston

  • Y.Y. Xue

    • Texas Center for Superconductivity and department of Physics, University of Houston, Houston, TX 77204-5002
    • TcSUH and Dept. of Physics, University of Houston

  • Z.P. Yin

    • Rutgers University
    • Dept. of Physics and Astronomy, Rutgers University

  • G. Kotliar

    • Rutgers University
    • Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08856-8019, USA
    • Rutgers Univ
    • Department of Physics and Astronomy, Rutgers University
    • Dept. of Physics and Astronomy, Rutgers University

  • Ching Wu Paul Chu

    • TcSUH and Dept. of Physics, University of Houston
    • TcSUH and Dept. of Physics, University of Houston; Lawrence Berkeley National Laboratory
    • Texas Center for Superconductivity and Department of Physics, University of Houston; Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley
    • Department of Physics, TcSUH, and Lawrence Berkeley National Laboratory