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arXiv · 0805.0676

Octupolar ordering of classical kagome antiferromagnets in two and three dimensions

M. E. Zhitomirsky
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Abstract

Classical Heisenberg antiferromagnets on two-dimensional kagome and three-dimensional hyperkagome lattices are investigated by Monte Carlo simulations. For both models the symmetry-breaking states at low temperatures are described by non-zero octupole moments or third-rank spin tensor order parameters. In the case of the two-dimensional kagome antiferromagnet, a sharp crossover into a coplanar state takes place at T_k ~ 0.004J, which we attribute to proliferation of fractional vortices. The three-dimensional model exhibits a first-order transition at T_c ~ 0.002J into a phase with critical spin correlations, which possesses a long-range order of octupole moments.

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M. E. Zhitomirsky. 2008-09-16. Octupolar ordering of classical kagome antiferromagnets in two and three dimensions. https://doi.org/10.1103/physrevb.78.094423

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