Determination of precession and dissipation parameters in the micromagnetism

The precession β and the dissipation parameter α of a ferromagnetic material can be considered microscopically space dependent. Their space distribution is difficult to obtain by direct measurements. We consider in this article an inverse problem, where we aim at recovering α and β from space measurements of the magnetization in the whole domain Ω. The evolution of the magnetization in micromagnetics is governed by the Landau-Lifshitz (LL) equation. We first study the sensitivity of the LL equation. On basis of the results we analyze the inverse problem. We support the theory by numerical examples