Spin order and fluctuations in FeSe

ORAL

Abstract

FeSe is the simplest Fe-based system. Depending on the environment, the superconducting transition temperature ranges between 9 and approximately 100 K. As opposed to the Fe pnictides, long range magnetic order is not found in FeSe. Yet, the charge and spin dynamics of FeSe may hold key information on the physics of high temperature superconductors in general. We report results of light scattering experiments as a function of polarization and temperature and simulate the spectra using exact diagonalization. With the parameters of a frustrated spin 1 Heisenberg model the experiment can be reproduced for all Raman active symmetries. We find a low energy peak in B1g symmetry and assign this feature to excitations of nearly localized spins. Comparable agreement between theory and experiment can be achieved for neutron scattering data. The study furnishes evidence for nearly frustrated spin order and critical fluctuations of spin stripes with an ordering vector close to or at (π,0).

*German Research Foundation (DFG): SPP1458 (HA2071/7), HA2071/8, Transregional Collaborative Research Center TRR80; Bavarian Californian Technology Center (BaCaTeC).

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Presenters

  • Rudolf Hackl

    • Walther Meissner Institut
    • Walther Meissner Inst

Authors

  • Rudolf Hackl

    • Walther Meissner Institut
    • Walther Meissner Inst

  • Andreas Baum

    • Walther Meissner Institut

  • Harrison Ruiz

    • Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory

  • Nenad Lazarevic

    • Institute of Physics Belgrade, University of Belgrade

  • Yao Wang

    • Department of Applied Physics, Stanford University
    • Harvard Univ
    • Physics, Harvard University
    • Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory

  • Thomas Boehm

    • Walther Meissner Institut

  • Ramez Hosseinian Ahangharnejhad

    • Walther Meissner Institut

  • Peter Adelmann

    • Karlsruhe Institute of Technology

  • Thomas Wolf

    • Institute of Solid State Physics (IFP), Karlsruhe Institute of Technology
    • Karlsruher Institut für Technologie
    • Karlsruhe Institute of Technology
    • IFP, Karlsruhe Institute of Technology

  • Zoran Popovic

    • Institute of Physics Belgrade, University of Belgrade

  • Brian Moritz

    • Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory

  • Thomas Devereaux

    • Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory
    • Stanford Univ
    • SLAC and Stanford University
    • SLAC National Accelerator Laboratory
    • SLAC - Natl Accelerator Lab
    • Stanford Institute for Materials and Energy Sciences, SLAC National Laboratory
    • Stanford University
    • SIMIS, Stanford University
    • Physics, Stanford University
    • SLAC National Lab and Stanford University
    • SIMES, SLAC and Stanford University