Quasi-elastic scattering from short-range magnetic order in FeTe<sub>1-x</sub>Se<sub>x</sub> compounds

ORAL

Abstract

We report neutron scattering measurements on single crystals of FeTe1-xSex. Superconductivity (SC) and antiferromagnetic (AFM) order in these compounds can be tuned together by varying Se compositions and/or excess Fe. We show that in systems where long-range magnetic order develops, superconductivity is completely suppressed. The long-range magnetic order is static with long life-time. On the other hand, when the magnetic order is short-range and the system exhibits behaviors of a mixed phase or phase separation between AFM and SC, the energy profile of the magnetic order appears to be quasi-elastic with energy widths around 0.2 meV. We discuss the evolution of the quasi-elastic magnetic scattering with temperature and doping, and their implications on the understanding of the spin-glass/SC mixed phase in FeTe1-xSex systems.

*The work at Brookhaven National Laboratory and
Lawrence Berkeley National Laboratory was supported by the
Office of Basic Energy Sciences (BES), Division of Materials
Science and Engineering, U.S. Department of Energy
(DOE), under Contracts No. DE-SC0012704 and No. DEAC02-
05CH1123, respectively.

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Presenters

  • Guangyong Xu

    • Center of Neutron Research, National Institute of Standards and Technology
    • Neutron-Condensed Matter Science Group, National Institute of Standards and Technology
    • National Institute of Standards and Technology
    • NIST
    • Center for Neutron Research, National Institute of Standards and Technology
    • NIST Center for Neutron Research
    • Oak Ridge National Laboratory

Authors

  • Guangyong Xu

    • Center of Neutron Research, National Institute of Standards and Technology
    • Neutron-Condensed Matter Science Group, National Institute of Standards and Technology
    • National Institute of Standards and Technology
    • NIST
    • Center for Neutron Research, National Institute of Standards and Technology
    • NIST Center for Neutron Research
    • Oak Ridge National Laboratory

  • Zhijun Xu

    • NIST and University of Maryland
    • National Institute of Standards and Technology
    • (NCNR, National Institute of Standards and Technology)
    • NIST Center for Neutron Research

  • Genda Gu

    • Brookhaven National Laboratory
    • Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory
    • Brookhaven national lab
    • Condensed Matter Physics and Materials Science, Brookhaven National Laboratory
    • Brookhaven National Lab
    • Condensed Matter Physics and Material Science, Brookhaven National Laboratory, Upton, NY, United States
    • Brookhaven National Laboratories
    • Condensed Matter Physics and Material Science Division, Brookhaven National Laboratory

  • John Tranquada

    • Brookhaven national lab
    • Brookhaven National Laboratory
    • Condensed Matter Physics & Materials Science Department, Brookhaven National Laboratory

  • Robert J Birgeneau

    • University of California, Berkeley
    • Physics, University of California at Berkeley
    • Physics, University of California, Berkeley
    • Department of Physics, University of California, Berkeley