Domain-wall dynamics in polycrystalline garnet and hexagonal materials

In the polycrystalline state, the interactions are more complicated and a specific spontaneous anisotropy was established there, called "total anisotropy". The work deals with the domain-wall (DW) mobility due to magnetoelastic and high anisotropy interactions. The effects of the magnetoelasic stress anisotropy in the Mn:YIG and shape anisotropy in the Ba-hexaferrite on the complex magnetic permeability spectrum mu*(f) were investigated in a broad frequency range (0.3 divided by 3 GHz). An attempt was made to adapt the "Domain-wall size" model to the explanation of domain wall dynamics in a weak high-frequency magnetic field. Some new data concerning the total anisotropy specifically for garnet and hexaferrite polycrystals were discussed and its value deduced from natural spin resonance measurements.