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Aging in a Two-Dimensional Ising Model with Dipolar Interactions

Julio H. Toloza·Francisco A. Tamarit·Sergio A. Cannas
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Abstract

Aging in a two-dimensional Ising spin model with both ferromagnetic exchange and antiferromagnetic dipolar interactions is established and investigated via Monte Carlo simulations. The behaviour of the autocorrelation function $C(t,t_w)$ is analyzed for different values of the temperature, the waiting time $t_w$ and the quotient $δ=J_0/J_d$, $J_0$ and $J_d$ being the strength of exchange and dipolar interactions respectively. Different behaviours are encountered for $C(t,t_w)$ at low temperatures as $δ$ is varied. Our results show that, depending on the value of $δ$, the dynamics of this non-disordered model is consistent either with a slow domain dynamics characteristic of ferromagnets or with an activated scenario, like that proposed for spin glasses.

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Julio H. Toloza, Francisco A. Tamarit, Sergio A. Cannas. 1998-05-27. Aging in a Two-Dimensional Ising Model with Dipolar Interactions. https://doi.org/10.1103/physrevb.58.r8885

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