Measurements of Interaction in an Assembly of γ-Iron Oxide Particles

Abstract

An experimental study of the statistical stability of the Preisach function is performed. The shape of the sample is varied in order to introduce an adjustable demagnetizing field to simulate various degrees of statistical instability. By choosing the proper shape it is possible to obtain a statistically stable distribution of interaction fields. Measurements of the standard deviation of interaction field show, just as calculations of the critical fields of the particles have shown, that the particles do not appear to switch as signal units.