Dynamical Magnetism and Orbital Selective Physics in 11 Iron Chalcogenides

ORAL

Abstract

There are profound connections between dynamical magnetism and unconventional superconductivity in Fe-based superconductors. Recently, new aspects associated with their multi-band, multi-orbital nature and the resulting orbital physics came to prominence in iron the chalcogenide family. While early neutron scattering experiments already presented indication of an orbital-selective electron localization and ferro-orbital order in the FeTe parent material [1,2], an orbital-selective Cooper pairing was recently discovered in the FeSe end member by STM [3]. Here, we present polarized neutron scattering studies of magnetic dynamics in FeTe parent material and FeTe0.45Se0.55 optimally doped superconductor, where we analyze the wave vector dependence of the magnetic form factor in order to understand the orbital state of magnetic electrons. Our results indicate an unusual, energy- and temperature-dependent orbital composition of dynamical magnetism revealed by polarized neutron spectroscopy.
[1] I. A. Zaliznyak, et. al., Phys. Rev. Lett. 107, 216403 (2011).
[2] D. Fobes, et. al., Phys. Rev. Lett. 112, 187202 (2014).
[3] P. O. Sprau, et al, Science 357, 75-80 (2018).

*Work at BNL is supported by the Office of Basic Energy Sciences, U.S. Department of Energy, under contract no. DE-SC0012704

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Presenters

  • Igor Zaliznyak

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

Authors

  • Igor Zaliznyak

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

  • Yangmu Li

    • Brookhaven National Laboratory

  • Andrei T Savici

    • Oak Ridge National Laboratory

  • Vasile O Garlea

    • Oak Ridge National Laboratory
    • Quantum Condensed Matter Div, Oak Ridge National Lab
    • Oak Ridge National Lab
    • Oak Ridge National Lab, Neutron Scattering Division

  • 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