A phenomenological model for the spontaneous exchange bias effect

TL;DR

This paper introduces a new phenomenological model to explain the spontaneous exchange bias effect in spin glass-like systems, accurately capturing temperature and field dependence by considering the dynamics of relaxing spin glass spins.

Contribution

It presents an improved model that better describes the SEB effect by estimating the relaxing spin glass spins during magnetic cycles, enhancing understanding of the phenomenon.

Findings

The model accurately reproduces the temperature dependence of SEB.

It explains the variation of SEB with different maximum applied fields.

The approach improves upon previous models by incorporating spin relaxation estimates.

Abstract

In this work we propose an alternative model to explain the spontaneous exchange bias (SEB) effect observed in spin glass (SG)-like systems. As in a previously proposed model (Ref. 1), it is based on the unconventional dynamics of the SG-like moments at the magnetic hysteresis cycle. However, using a reliable estimate of the amount of SG-spins that are relaxing during the cycle, the new model can correctly describe the changes in the SEB observed for measurements performed at different temperatures and different maximum applied fields.