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Spatially anisotropic Heisenberg Kagome antiferromagnet

W. Apel·T. Yavors'kii·H. -U. Everts
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Abstract

In the search for spin-1/2 kagome antiferromagnets, the mineral volborthite has recently been the subject of experimental studies [Hiroi et al.,2001]. It has been suggested that the magnetic properties of this material are described by a spin-1/2 Heisenberg model on the kagome lattice with spatially anisotropic exchange couplings. We report on investigations of the Sp(N) symmetric generalisation of this model in the large N limit. We obtain a detailed description of the dependence of possible ground states on the anisotropy and on the spin length S. A fairly rich phase diagram with a ferrimagnetic phase, incommensurate phases with and without long range order and a decoupled chain phase emerges.

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W. Apel, T. Yavors'kii, H. -U. Everts. 2006-08-17. Spatially anisotropic Heisenberg Kagome antiferromagnet. https://doi.org/10.1088/0953-8984%2F19%2F34%2F349001

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