Inelastic neutron scattering studies on spin excitations of Fe Pnictides

ORAL

Abstract

We used inelastic neutron scattering to study the evolution of spin excitations in the FeAs superconductors and their parent compounds. We show here not only the antiferromagnetic order is suppressed by the doping; the spin excitations also change dramatically with doping. We observed sharp spin-wave excitations in the antiferromagnetically ordered parent compound. Based on the observed dispersion relation, we estimate the effective magnetic exchange coupling using a Heisenberg model. We also studied the spin excitation spectrum in the superconducting sample and its relationship to the superconductivity.

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Authors

  • Jun Zhao

    Department of Physics and Astronomy, The University of Tennessee, University of Tennessee, Knoxville

  • Dao-Xin Yao

    Department of Physics, Purdue University, Purdue University

  • Shiliang Li

    Department of Physics and Astronomy, The University of Tennessee, University of Tennessee, Knoxville, University of Tennessee

  • Tao Hong

    Oak Ridge National Laboratory, Neutron Scattering Science Division, Oak Ridge National Laboratory

  • Ying Chen

    NCNR and Univ. of Maryland, NIST Center for Neutron Research, National Institute of Standards and Technology, NIST Center for Neutron Research, University of Maryland

  • Sung Chang

    NIST Center for Neutron Research, National Institute of Standards and Technology

  • William Ratcliff,

    NIST, NIST Center for Neutron Research, National Institute of Standards and Technology, National Institute of Standards and Technology

  • Jeff Lynn

    NIST Center for Neutron Research, National Institute of Standards and Technology

  • Herbert Mook

    Neutron Scattering Science Division, Oak Ridge National Laboratory, NSSD-ORNL

  • Gen Fu Chen

    Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Institute of Physics, Chinese Academy of Sciences

  • Jian Lin Luo

    Institute of Physics, Chinese Academy of Science, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Institute of Physics, Chinese Academy of Sciences

  • Nan Lin Wang

    Institute of Physics, Chinese Academy of Science, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, Institute of Physics, Chinese Academy of Sciences

  • Erica Carlson

    Department of Physics, Purdue University

  • Jiangping Hu

    Purdue University, Department of Physics, Purdue University

  • Pengcheng Dai

    Department of Physics and Astronomy, The University of Tennessee \& Neutron Scattering Science Division, Oak Ridge National Laboratory