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Two-dimensional behavior of the sublattice magnetization in three-dimensional Ising antiferromagnets

O. Petracic·Ch. Binek·W. Kleemann
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Abstract

A three-dimensional layered Ising-Antiferromagnet with a ferromagnetic intra-layer coupling to z neighbors, zJ > 0, and an antiferromagnetic interlayer coupling to z' neighbors, z'J' < 0, is investigated by Monte Carlo simulations on a hexagonal lattice. The physical nature of the anomalous temperature bahavior of the sublattice magnetizations, which is found for certain values of r=zJ/z'J' and z' in magnetic fields is explained in terms of successive phase transitions. They take place on the ferromagnetic 2-dimensional spin-down sublattice at T = T_c^{2d}, smeared by a finite stabilizing molecular field, and on both antiferromagnetically coupled sublattices at T_c^{3d} > T_c^{2d}.

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O. Petracic, Ch. Binek, W. Kleemann. 1999-06-01. Two-dimensional behavior of the sublattice magnetization in three-dimensional Ising antiferromagnets. https://doi.org/10.1142/9789812793652_0030

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