Kinetic effects observed in dynamic FORCs of magnetic wires: Experiment and theoretical description

TL;DR

This paper extends the FORC diagram method to rate-dependent hysteresis in magnetic wires, combining experimental measurements with a domain wall movement model to accurately describe the observed kinetic effects.

Contribution

It introduces a new model based on domain wall dynamics that effectively simulates rate-dependent FORC diagrams in amorphous magnetic wires.

Findings

The model accurately describes experimental FORC diagrams.

Experimental FORCs vary with field-rate, revealing kinetic effects.

Some details in FORC diagrams are not captured by the model.

Abstract

This study is focused on the possibility to extend the use of the first-order reversal curve (FORC) diagram method to rate-dependent hysteresis. The FORCs for an amorphous magnetic wire was measured with an inductometric experimental setup in which the field-rate was maintained constant. The FORC experiment was performed for four different field-rates. As it is known, to obtain quantitative information on the magnetization process during the FORC process we need a model able to simulate as close as possible the experimental FORC diagrams. In this case, we have developed and implemented a model based on the hypothesis that the magnetization processes in this kind of materials are mainly due to the movement of a domain wall between the central domains of the wire. The differential equation of the domain wall movement is able to give a remarkably accurate description of the experimental FORC diagrams. The experimental FORCs, the FORC susceptibility diagram and the classical FORC diagram show however a number of details that the model is not able to describe. In each such case one discuss the possible physical cause of the observed behavior. As the magnetic wires are analyzed in many laboratories around the world for a wide variety of applications (essentially involving the control of the domain wall movement) we consider that our study offers to these researchers a valuable new tool.