Phase diagrams of a classical two-dimensional Heisenberg antiferromagnet with single-ion anisotropy

R. Leidl; W. Selke

doi:10.1103/physrevb.70.174425

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Phase diagrams of a classical two-dimensional Heisenberg antiferromagnet with single-ion anisotropy

R. Leidl·W. Selke

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Abstract

A classical variant of the two-dimensional anisotropic Heisenberg model reproducing inelastic neutron scattering experiments on La_5 Ca_9 Cu_24 O_41 [M. Matsuda et al., Phys.Rev. B 68, 060406(R) (2003)] is analysed using mostly Monte Carlo techniques. Phase diagrams with external fields parallel and perpendicular to the easy axis of the anisotropic interactions are determined, including antiferromagnetic and spin-flop phases. Mobile spinless defects, or holes, are found to form stripes which bunch, debunch and break up at a phase transition. A parallel field can lead to a spin-flop phase.

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R. Leidl, W. Selke. 2004-09-21. Phase diagrams of a classical two-dimensional Heisenberg antiferromagnet with single-ion anisotropy. https://doi.org/10.1103/physrevb.70.174425

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