Eigenmodes of twisted spin-waves in a thick ferromagnetic nanodisk
arXiv:2201.08621 · doi:10.1016/j.jmmm.2022.169762
Abstract
Magnetic vortex is topologically nontrivial and commonly found in ferromagnetic nanodisks. So far, three classes spin-wave eigenmodes, i.e., gyrotropic, azimuthal and radial modes, have been identified in ferromagnetic nanodisks. Here, using micromagnetic simulation and analytical calculation, we reveal twisted spin-wave modes in a thick permalloy (Ni0.8Fe0.2) nanodisk. The twisted spin-waves carry topological charges, which sign depends on the core polarity of the magnetic vortex in the nanodisk. By applying rotating magnetic fields at one end of the sample, we observe continuous generation of twisted spin-waves that have characteristic spiral phase front and carry topological charge l = 1, -1, 2 and -2. The dispersion relation of twisted spin-waves is derived analytically and the result is in good agreement with micromagnetic numerical calculations.
References in corpus (6)
- Magnetic Vortex Core Reversal by Excitation of Spin Waves
- Vortex state oscillations in soft magnetic cylindrical dots
- Coherent excitation of heterosymmetric spin waves with ultrashort wavelengths
- Twisted magnon as a magnetic tweezer
- Dynamics of Spiral Spin Waves in Magnetic Nano-patches: Influence of Thickness and Shape
- Spin dynamics of anisotropic azimuthal modes in heterogeneous magnetic nanodisks