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

TL;DR

This study uses Monte Carlo simulations to explore the complex temperature-dependent behavior of sublattice magnetizations in a layered 3D Ising antiferromagnet, revealing successive phase transitions influenced by interlayer and intralayer couplings.

Contribution

It provides a detailed analysis of the two-dimensional behavior of sublattice magnetizations in a three-dimensional Ising antiferromagnet, highlighting the nature of phase transitions.

Findings

Identification of successive phase transitions at T_c^{2d} and T_c^{3d}.

Explanation of anomalous magnetization behavior in terms of phase transitions.

Impact of coupling ratios and magnetic fields on sublattice magnetization behavior.

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}.