Spin excitation spectra in helimagnetic states: Proper-screw, cycloid, vortex-crystal, and hedgehog lattices

  title={Spin excitation spectra in helimagnetic states: Proper-screw, cycloid, vortex-crystal, and hedgehog lattices},
  author={Yasuyuki Kato and Satoru Hayami and Yukitoshi Motome},
  journal={Physical Review B},
We investigate the spin excitation spectra in chiral and polar magnets by the linear spin-wave theory for an effective spin model with symmetric and antisymmetric long-range interactions. In one dimension, we obtain the analytic form of the dynamical spin structure factor for proper-screw and cycloidal helical spin states with uniform twists, which shows a gapless mode with strong intensity at the helical wave number. When introducing spin anisotropy in the symmetric interactions, we… 
1 Citations
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  • S. Hayami, Y. Motome
  • Physics, Medicine
    Journal of physics. Condensed matter : an Institute of Physics journal
  • 2021
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