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arXiv · 0705.1935

Field induced tricritical behavior in the S=1/2 quasi one-dimensional frustrated Ising antiferromagnet

E. Meloche·M. L. Plumer
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Abstract

The results of extensive histogram cluster heat-bath Monte Carlo simulations on the critical behavior of the quasi-one dimensional Ising antiferromagnet on a stacked triangular lattice are presented. A small applied field is shown to induce a crossover from XY universality to mean-field tricritical behavior. Experimental estimates of critical exponents suggest that these two types of phase transitions are observed in S=1 CsNiCl$_3$ and $S=1/2$ CsCoBr$_3$, respectively. The present results demonstrate that this difference can be explained by an unusual staggered magnetic field arising from quantum exchange mixing previously proposed to account for spin excitations in $S=1/2$ quasi-one-dimensional Ising antiferromagnets.

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E. Meloche, M. L. Plumer. 2007-05-14. Field induced tricritical behavior in the S=1/2 quasi one-dimensional frustrated Ising antiferromagnet. https://arxiv.org/abs/0705.1935

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