Anisotropic spin excitations in detwinned parent iron pnictides

ORAL

Abstract

Motivated by recent inelastic neutron scattering measurement on the fully detwinned BaFe2As2, we study the spin excitations of a local-moment model in the (π,0) collinear antiferromagnetically ordered phase. We show that the spin quadrupole modes can provide significant contributions to the spin excitation spectrum at high energies, and demonstrate this effect in an S=1 frustrated spin model with bilinear-biquadratic interactions using a flavor wave approach in an SU(3) representation. As a combined effect of the magnons and quadrupole modes, the spin excitation anisotropy drops with increasing energy. Our results are in good agreement with the salient features of the experimental observation.

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Presenters

  • Qimiao Si

    Rice University, Department of Physics and Astronomy, Rice University, Department of Physics and Astronomy, Houston, Texas 77005, USA, Rice University

Authors

  • Qimiao Si

    Rice University, Department of Physics and Astronomy, Rice University, Department of Physics and Astronomy, Houston, Texas 77005, USA, Rice University

  • Changle Liu

    Department of Physics, Fudan University, Fudan University

  • Xingye Lu

    Center for advanced quantum studies and Department of physics, Beijing Normal University, China, Beijing Normal University

  • Pengcheng Dai

    Rice University, Department of Physics and Astronomy, Rice University, Department of Physics and Astronomy, Rice University, Houston, TX 77005, USA

  • Rong Yu

    Renming University of China, Physics Department, Renmin University, Renmin University of China, Department of Physics, Renmin University of China