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Spin-glass behavior in the random-anisotropy Heisenberg model

Orlando V. Billoni·Sergio A. Cannas·Francisco A. Tamarit
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Abstract

We perform Monte Carlo simulations in a random anisotropy magnet at a intermediate exchange to anisotropy ratio. We focus on the out of equilibrium relaxation after a sudden quenching in the low temperature phase, well below the freezing one. By analyzing both the aging dynamics and the violation of the Fluctuation Dissipation relation we found strong evidence of a spin--glass like behavior. In fact, our results are qualitatively similar to those experimentally obtained recently in a Heisenberg-like real spin glass.

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Orlando V. Billoni, Sergio A. Cannas, Francisco A. Tamarit. 2005-09-20. Spin-glass behavior in the random-anisotropy Heisenberg model. https://doi.org/10.1103/physrevb.72.104407

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