Interactions between grain boundaries and magnetic domains of Ferrites

The magnetostatic energy E
m
in bulk materials containing inhomogeneities cannot be neglected. Its significance suggests an approach similar to the domains in magnetic thin films. As a first approximation, the domain wall is assumed to be planar and its propagation one-dimensional. Examples of grain boundary parallel and perpendicular to the domain wall were illustrated. Next, the planar constraint on the domain wall was relaxed. The domain subwalls were assumed to move sinusoidally in its length. For an assumed path of domain wall movement, the energetics of the energy terms E
EX
, E
AN
, and E
m
were evaluated. The motion is similar to the recently proposed new mode of Néel wall motion by Slonczewski, namely, the Néel-wall breathing. The motion becomes two-dimensional in its propagations.