Magnetic Anisotropy from the Magnetostatic Modes

Abstract

The differential equations for the magnetostatic modes in ferrimagnetic resonance have been rederived including the anisotropy torques. Exact solutions have been obtained for four of the low order modes of a sphere. These solutions differ in general from those for the differential equations not including anisotropy. Excellent agreement was found between measured resonance fields and those predicted by the modified theory.