Large downward renormalization of spin excitation energies in Ba<sub>1-x</sub>K<sub>x</sub>Fe<sub>2</sub>As<sub>2</sub> due to electron correlation effects

ORAL

Abstract

We report inelastic neutron scattering (INS) study of hole-doped iron-based superconductor Ba1-xKxFe2As2 (x = 0.25). The INS data show a spin-wave-like dispersive feature, with a zone boundary energy of 200 meV. A random phase approximation (RPA) treatment of the dynamical spin susceptibility, incorporating the band renormalization factor of 3 derived from angle-resolved photoemission spectroscopy (ARPES) measurements on the same sample, provides a reasonable description of the observed spin excitations. This analysis shows that the Fe-3d bandwidth narrowing due to electron correlation is directly reflected in the spin excitation energy scale. We will discuss the current state of our analysis relating the magnetic response to the underlying electronic structure of the materials.

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Presenters

  • Naoki Murai

    • Materials and Life Science Division, J-PARC Center, Japan Atomic Energy Agency

Authors

  • Naoki Murai

    • Materials and Life Science Division, J-PARC Center, Japan Atomic Energy Agency

  • Katsuhiro Suzuki

    • Research Organization of Science and Technology, Ritsumeikan University

  • Shin-ichiro Ideta

    • UVSOR Facility, Institute for Molecular Science

  • Masamichi Nakajima

    • Department of Physics, Osaka University

  • Hiroaki Ikeda

    • Ritsumeikan Univ
    • Department of Physics, Ritsumeikan University

  • Kiyohisa Tanaka

    • UVSOR Facility, Institute for Molecular Science

  • Ryoichi Kajimoto

    • Materials and Life Science Division, J-PARC Center, Japan Atomic Energy Agency