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

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 نشر من قبل Andrea Maiorano
 تاريخ النشر 2008
  مجال البحث فيزياء
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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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