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arXiv · 0705.1517

Weak first order transition in the three-dimensional site-diluted Ising antiferromagnet in a magnetic field

A. Maiorano·V. Martín-Mayor·J. J. Ruiz-Lorenzo·A. Tarancón
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Abstract

We perform intensive numerical simulations of the three-dimensional site-diluted Ising antiferromagnet in a magnetic field at high values of the external applied field. Even if data for small lattice sizes are compatible with second-order criticality, the critical behavior of the system shows a crossover from second-order to first-order behavior for large system sizes, where signals of latent heat appear. We propose "apparent" critical exponents for the dependence of some observables with the lattice size for a generic (disordered) first-order phase transition.

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A. Maiorano, V. Martín-Mayor, J. J. Ruiz-Lorenzo, A. Tarancón. 2008-02-14. Weak first order transition in the three-dimensional site-diluted Ising antiferromagnet in a magnetic field. https://doi.org/10.1103/physrevb.76.064435

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