Metastable random-field Ising model with exchange enhancement: A simple model for exchange bias

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...

ver descrição completa

Detalhes bibliográficos
Autores: Illa i Tortós, Xavier, Vives i Santa-Eulàlia, Eduard, Planes Vila, Antoni
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2002
País:España
Recursos:Universidad de Barcelona
Repositório:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/10537
Acesso em linha:https://hdl.handle.net/2445/10537
Access Level:Acceso aberto
Palavra-chave:Histèresi
Model d'Ising
Vidres de spin
Hysteresis
Ising model
Spin glasses
Descrição
Resumo: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 neighboring 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 $\ensuremath{\sigma}$ of the Gaussian distribution of the random fields.