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Metastable Random Field Ising model with exchange enhancement: a simple model for Exchange Bias

Xavier Illa·Eduard Vives·Antoni Planes
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Abstract

We present a simple model that allows hysteresis loops with exchange bias to be reproduced. The model is a modification of the T=0 random field Ising model driven by an external field and with synchronous local relaxation dynamics. The main novelty of the model is that a certain fraction f of the exchange constants between neighbouring spins is enhanced to a very large value J_E. The model allows the dependence of the exchange bias and other properties of the hysteresis loops to be analyzed as a function of the parameters of the model: the fraction f of enhanced bonds, the amount of the enhancement J_E and the amount of disorder which is controlled by the width sigma of the Gaussian distribution of the random fields.

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Xavier Illa, Eduard Vives, Antoni Planes. 2002-08-01. Metastable Random Field Ising model with exchange enhancement: a simple model for Exchange Bias. https://doi.org/10.1103/physrevb.66.224422

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