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arXiv · 1209.2520

Second-order phase transition in the Heisenberg model on a triangular lattice with competing interactions

Ryo Tamura·Shu Tanaka·Naoki Kawashima
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Abstract

We discover an example where the dissociation of the Z2 vortices occurs at the second-order phase transition point. We investigate the nature of phase transition in a classical Heisenberg model on a distorted triangular lattice with competing interactions. The order parameter space of the model is SO(3)xZ2. The dissociation of the Z2 vortices which comes from SO(3) and a second-order phase transition with Z2 symmetry breaking occur at the same temperature. We also find that the second-order phase transition belongs to the universality class of the two-dimensional Ising model.

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Ryo Tamura, Shu Tanaka, Naoki Kawashima. 2012-09-12. Second-order phase transition in the Heisenberg model on a triangular lattice with competing interactions. https://doi.org/10.1103/physrevb.87.214401

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