Spin-charge coupling in a band ferromagnet: Magnon-energy reduction, anomalous softening, and damping

  title={Spin-charge coupling in a band ferromagnet: Magnon-energy reduction, anomalous softening, and damping},
  author={Sudhakar Pandey and Avinash Singh},
  journal={Physical Review B},
The effects of correlation-induced coupling between spin and charge fluctuations on spin-wave excitations in a band ferromagnet are investigated by including self-energy and vertex corrections within a systematic inverse-degeneracy expansion scheme which explicitly preserves the Goldstone mode. Arising from the scattering of a magnon into intermediate spin-excitation states (including both magnon and Stoner excitations) accompanied with charge fluctuations in the majority-spin band, this spin… 
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