New Theory of Coercive Force of Ferromagnetic Materials

Abstract

We have enlarged the theory of the coercive force to include the wave nature of the ferromagnetic domain walls. Specifically, we obtain an explicit equation for the magnetic field required to move a 180\ifmmode^\circ\else\textdegree\fi{} ferromagnetic domain wall across a planar defect such as a grain boundary. Using this expression, we have been able to classify successfully both low- and high-coercive-force materials.