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Is demagnetization an efficient optimization method?

S. Zapperi·F. Colaiori·L. Dante·V. Basso·G. Durin·A. Magni·M. J. Alava
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Abstract

Demagnetization, commonly employed to study ferromagnets, has been proposed as the basis for an optimization tool, a method to find the ground state of a disordered system. Here we present a detailed comparison between the ground state and the demagnetized state in the random field Ising model, combing exact results in $d=1$ and numerical solutions in $d=3$. We show that there are important differences between the two states that persist in the thermodynamic limit and thus conclude that AC demagnetization is not an efficient optimization method.

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S. Zapperi, F. Colaiori, L. Dante, V. Basso, G. Durin, A. Magni, M. J. Alava. 2005-07-13. Is demagnetization an efficient optimization method?. https://doi.org/10.1016/j.jmmm.2003.12.627

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