Spin waves in a ferromagnetic nanoshell. Consideration of the dissipation effects in the shortwave approximation
Keywords:
ferromagnetic nanoshell, spin excitation, dipole-exchange theoryAbstract
In the paper, spin excitations in a nanoshell comprised of an uniaxial ferromagnet of the "easy axis" type are investigated theoretically. For dipole-exchange excitations, an equation for the magnetic potential in magnetostatic approximation is obtained with accounting for the dissipative effects and the anisotropy. For short-wave spin excitations, a dispersion relation, a characteristic damping time and a radial wavenumber spectrum is obtained. Limitations on the number of possible radial and azimuthal modes of spin excitations are obtained. It is shown (via numerical evaluations) that the short-wave approximation used in the paper is applicable for typical nanoshells.References
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