Possible multiple modes of neutron spin resonance in Ba<sub>1-x</sub>K<sub>x</sub>Fe<sub>2</sub>As<sub>2</sub> and BaFe<sub>2-x</sub>Ni<sub>x</sub>As<sub>2</sub>

ORAL

Abstract

Motivated by the triple modes of neutron spin resonance with both odd and even L-symmetries in CaKFe4As4[1],we use inelasitc neutron scattering to re-investigate the spin resonance in 122 system of iron-based superconductors. In the optimally hole doped Ba1-xKxFe2As2, the spin resonance has very weak L-dependence both for intensity and center energy, while the H-dependence show a combination with an incommensurate mode at high energy and a commensurate mode at low energy. In the optimally electron doped BaFe2-xNixAs2, the spin resonance becomes L-dependent at low energy. A very weak even mode (L=2,4, 6...) probably exist around 14 meV. Therefore, in contrast to the explaination based on weak L-dispersion on single spin resonance mode, we propose an alternative explanation based on the multiply Fermi surface nesting induced multi-modes with different symmetries, which give Q-dependent intensity either for out-of-plane or in-plane spin excitations.

[1] T. Xie et al., Phys. Rev. Lett. 120, 267003 (2018)

*This work is supported by NSFC, MOST and CAS.

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Presenters

  • Sergey Danilkin

    • Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization

Authors

  • Huiqian Luo

    • Institute of Physics, Chinese Academy of Sciences

  • Tao Xie

    • Institute of Physics, Chinese Academy of Sciences
    • National Lab for superconductivity, Institute of Physics, Chinese Academy of Sciences, Beijing, China

  • Shiliang Li

    • National Laboratory for Superconductivity, Institute of Physics,Chinese Academy of Sciences
    • Institute of Physics, Chinese Academy of Sciences
    • National Lab for superconductivity, Institute of Physics, Chinese Academy of Sciences, Beijing, China

  • Uwe Stuhr

    • Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute

  • Tom Fennell

    • paul scherrer insitute
    • Paul Scherrer Institute
    • Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, Villigen
    • Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute

  • Sergey Danilkin

    • Australian Centre for Neutron Scattering, Australian Nuclear Science and Technology Organization