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Domain-Wall Energies and Magnetization of the Two-Dimensional Random-Bond Ising Model

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 نشر من قبل Carlo Amoruso
 تاريخ النشر 2004
  مجال البحث فيزياء
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We study ground-state properties of the two-dimensional random-bond Ising model with couplings having a concentration $pin[0,1]$ of antiferromagnetic and $(1-p)$ of ferromagnetic bonds. We apply an exact matching algorithm which enables us the study of systems with linear dimension $L$ up to 700. We study the behavior of the domain-wall energies and of the magnetization. We find that the paramagnet-ferromagnet transition occurs at $p_c sim 0.103$ compared to the concentration $p_nsim 0.109$ at the Nishimory point, which means that the phase diagram of the model exhibits a reentrance. Furthermore, we find no indications for an (intermediate) spin-glass ordering at finite temperature.



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