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arXiv · 1606.05076

Tricritical behaviour of the frustrated Ising antiferromagnet on the honeycomb lattice

A. Bobák·T. Lučivjanský·M. Žukovič·M. Borovský·T. Balcerzak
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Abstract

We use the effective-field theory with correlations based on different cluster sizes to investigate phase diagrams of the frustrated Ising antiferromagnet on the honeycomb lattice with isotropic interactions of the strength $J_1 < 0$ between nearest-neighbour pairs and $J_2 < 0$ between next-nearest neighbour pairs of spins. We present results for the ground-state energy as a function of the frustration parameter $R = J_2 /|J_1|$. We find that the cluster-size has a considerable effect on the existence and location of a tricritical point in the phase diagram at which the phase transition changes from the second order to the first one.

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A. Bobák, T. Lučivjanský, M. Žukovič, M. Borovský, T. Balcerzak. 2016-06-16. Tricritical behaviour of the frustrated Ising antiferromagnet on the honeycomb lattice. https://doi.org/10.1016/j.physleta.2016.06.019

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