The Limitation of Anticipation by First Order Reversal Curve Method

Abstract

The magnetic hysteresis loops have been mathematically interpreted by the classical Preisach model assuming that the magnetic materials are composed of many of hysterons. The hysteron is defined as hysteresis elements having bistable state. The distribution of switching field of these hysterons gives information of the interaction in the system. First order reversal curve (FORC) analysis proposed by Mayergoyz [1] is successive tool to understand reversal mechanism, and interactions in magnetic system by extracting switching distributions from additional reversal curves. Because of the convenience of extracting switching distributions, FORC method has been utilized for investigating the magnetic materials such as permanent magnets [2-3] and their temperature dependence [4], or alloy structure [5]. However, there is a clear limitation for investigating magnetic materials by using FORC methods based on classical Preisach model. This is arising from the basic assumption, there are only bistable states of each hysteron, even though most of magnetic systems are comprised of vector magnetic moments. In this presentation, we will clearly show the limitation anticipation by FORC method by comparing the switching field distributions from FORC method with the switching field obtained from full hysteresis loops of all grains in micromagnetic simulations [6]. There is a broad distinction between two kinds of the switching distributions not only displacement of the loops, but also the coercivity.