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arXiv · 1506.03813

Emergent Power-Law Phase in the 2D Heisenberg Windmill Antiferromagnet: A Computational Experiment

Bhilahari Jeevanesan·Premala Chandra·Piers Coleman·Peter P. Orth
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Abstract

In an extensive computational experiment, we test Polyakov's conjecture that under certain circumstances an isotropic Heisenberg model can develop algebraic spin correlations. We demonstrate the emergence of a multi-spin $\text{U(1)}$ order parameter in a Heisenberg antiferromagnet on interpenetrating honeycomb and triangular lattices. The correlations of this relative phase angle are observed to decay algebraically at intermediate temperatures in an extended critical phase. Using finite-size scaling, we show that both phase transitions are of the Berezinskii-Kosterlitz-Thouless type and at lower temperatures, we find long-range $\mathbb{Z}_6$ order.

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Bhilahari Jeevanesan, Premala Chandra, Piers Coleman, Peter P. Orth. 2015-06-11. Emergent Power-Law Phase in the 2D Heisenberg Windmill Antiferromagnet: A Computational Experiment. https://doi.org/10.1103/physrevlett.115.177201

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