Statistical properties of pinning fields in the 3d-Gaussian RFIM

TL;DR

This paper investigates the statistical behavior of pinning fields in the 3D Gaussian RFIM, revealing critical behavior near coercivity and strong correlations, with implications for understanding magnetic hysteresis.

Contribution

It provides a detailed analysis of pinning field statistics in the Gaussian RFIM, highlighting their critical behavior and correlations near coercivity, which was not previously characterized.

Findings

Pinning fields increase sharply near the coercive field.

Discontinuous change in pinning fields occurs at low disorder levels.

Strong statistical correlations exist among pinning fields near coercivity.

Abstract

We have defined pinning fields as those random fields that keep some of the magnetic moments unreversed in the region of negative external applied field during the demagnetizing process. An analysis of the statistical properties of such pinning fields is presented within the context of the Gaussian Random Field Ising Model (RFIM). We show that the average of the pinning fields exhibits a drastic increase close to the coercive field and that such an increase is discontinuous for low degrees of disorder. This behaviour can be described with standard finite size scaling (FSS) assumptions. Furthermore, we also show that the pinning fields corresponding to states close to coercivity exhibit strong statistical correlations.