MAGNETOSTATIC VOLUME WAVES IN DIELECTRIC LAYERED STRUCTURE - EFFECT OF MAGNETOCRYSTALLINE ANISOTROPY

This paper presents a theoretical investigation of the effect of magnetocrystalline anisotropy on the group delay of magnetostatic volume waves in a layered structure consisting of a normally magnetized ferrite slab (or film) supported on one side by a metal-backed dielectric slab. The cases of cubic, as well as hexagonal, planar anisotropy have been considered. Numerical calculations for YIG (yttrium-iron-garnet) (cubic) and Zn2Y (planar) ferrites show that, in general, the magnetocrystalline anisotropy leads to anisotropic propagation in the plane of the slab and also affects the frequency range of nondispersive delay as well as the overall magnitude of group delay time. In the case of cubic ferrites, the specific crystallographic orientations have been obtained for which the effect of magnetocrystalline anisotropy on propagation characteristics is negligible. In the case of the Zn2Y planar ferrite, the frequency range of allowed modes is found to be extremely large; it extends from about 3 to 12 GHz, with an effective bias field as low as 200 Oe.