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Dipolar random field Ising model: an application to garnet films

Alessandro Magni·Gabor Vertesy
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Abstract

The dipolar-random field Ising model (DRFIM) recently introduced displays a behaviour that can be connected to the magnetization of bidimensional magnetic media. Epitaxial magnetic garnet films seem to be the ideal test material for such a model. In this work the results of the measurements performed on garnet samples are presented, as well as the comparisons with simulation results obtained by the DRFIM. The results prove that a variety of hysteresis loops are well described by the DRFIM. This capability does not derive from the fine tuning of a great number of parameters, but by the interplay of exchange and dipolar interactions.

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Alessandro Magni, Gabor Vertesy. 1999-07-06. Dipolar random field Ising model: an application to garnet films. https://doi.org/10.1103/physrevb.61.3203

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