The Tensor Formulation of Ferromagnetic Resonance

Abstract

The tensor formulation of electromagnetic wave propagation in a conducting ferromagnetic medium is used to describe resonance phenomena in a test cavity under two different conditions of magnetization. The new formulation alters the prediction with respect to the shape of the resonance curve in the case of perpendicular magnetization and it predicts a different ratio of energy absorptions in the cases of parallel and perpendicular magnetization than is given by a formulation based on the concept of a permeability coefficient. When interpreted according to the new formulation the results of simultaneous measurements of frequency shift and energy absorption under different conditions of magnetization are found to be consistent with each other. Such consistency is not achieved on the basis of earlier formulations.