Metamagnets in uniform and random fields

Serge Galam; Carlos S. O. Yokoi; Silvio R. Salinas

doi:10.1103/physrevb.57.8370

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Metamagnets in uniform and random fields

Serge Galam·Carlos S. O. Yokoi·Silvio R. Salinas

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Abstract

We study a two-sublattice Ising metamagnet with nearest and next-nearest-neighbor interactions, in both uniform and random fields. Using a mean-field approximation, we show that the qualitative features of the phase diagrams are significantly dependent on the distribution of the random fields. In particular, for a Gaussian distribution of random fields, the behavior of the model is qualitatively similar to a dilute Ising metamagnet in a uniform field.

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Serge Galam, Carlos S. O. Yokoi, Silvio R. Salinas. 1999-01-19. Metamagnets in uniform and random fields. https://doi.org/10.1103/physrevb.57.8370

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