Mixed spin-1/2 and spin-1 Ising ferromagnets on a triangular lattice

Milan Žukovič; Andrej Bobák

doi:10.1016/j.physa.2015.05.077

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arXiv · 1412.5811

Mixed spin-1/2 and spin-1 Ising ferromagnets on a triangular lattice

Milan Žukovič·Andrej Bobák

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Abstract

By Monte Carlo simulations we study critical properties of the mixed spin-1/2 and spin-1 Ising model on a triangular lattice, considering two different ways of the spin-value distributions on the three sublattices: $(1/2,1/2,1)$ and $(1/2,1,1)$. In the former case, we find standard Ising universality class phase transitions between paramagnetic and magnetic phases but no phase transitions between two distinct magnetic phases $(\pm 1/2,\pm 1/2,\pm 1)$ and $(\pm 1/2,\pm 1/2,0)$ at any finite temperature, except for some interesting non-critical anomalies displayed by response functions. On the other hand, the latter case turns out to be a rare (or perhaps the only) example of a two-dimensional mixed spin-1/2 and spin-1 Ising model on a standard lattice that displays tricritical behavior.

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Milan Žukovič, Andrej Bobák. 2014-12-18. Mixed spin-1/2 and spin-1 Ising ferromagnets on a triangular lattice. https://doi.org/10.1016/j.physa.2015.05.077

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