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arXiv · 0805.0983

Phase diagram of the Ising square lattice with competing interactions

A. Kalz·A. Honecker·S. Fuchs·T. Pruschke
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Abstract

We restudy the phase diagram of the 2D-Ising model with competing interactions $J_1$ on nearest neighbour and $J_2$ on next-nearest neighbour bonds via Monte-Carlo simulations. We present the finite temperature phase diagram and introduce computational methods which allow us to calculate transition temperatures close to the critical point at $J_2 = 0.5 J_1$. Further on we investigate the character of the different phase boundaries and find that the transition is weakly first order for moderate $J_2 > 0.5 J_1$.

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A. Kalz, A. Honecker, S. Fuchs, T. Pruschke. 2008-09-15. Phase diagram of the Ising square lattice with competing interactions. https://doi.org/10.1140/epjb/e2008-00359-6

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