Tricritical behaviour of the frustrated Ising antiferromagnet on the honeycomb lattice

A. Bobák; T. Lučivjanský; M. Žukovič; M. Borovský; T. Balcerzak

doi:10.1016/j.physleta.2016.06.019

paper

Tricritical behaviour of the frustrated Ising antiferromagnet on the honeycomb lattice

arXiv:1606.05076 · doi:10.1016/j.physleta.2016.06.019

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.

Figures can be obtained from T. Lučivjanský ([email protected]); 15 pages, 5 figures, pdf-Latex. arXiv admin note: text overlap with arXiv:1503.05094