Scientia Plena

Aplicação do método de Monte Carlo para o problema de ligações mistas em uma rede cúbica

J.B. Santos-Filho, Douglas F. de Albuquerque, A.S. de Arruda, N. O. Moreno

Published Jan 1, 2006• 0 citations

Abstract

The phase transition of a random mixed-bond Ising ferromagnet on a cubic lattice model is studied bothnumerically and analytically. Analytical studies on Mixed-bond Ising model by using renormalizationgroup technique predict the existence of reentrant magnetism in a certain range of values of thecompetition parameter α. This phenomenon typically is found in systems presenting spin glass phase, forinstance EupSr1-p. We seek the existence of the reentrance by means of Monte Carlo simulations. In thiswork, we use the Cluster algorithms de Wolff to simulate the dynamics of the system. We obtained thethermodynamic quantities such as magnetization and susceptibility. Critical temperatures were estimatedof the maximum of the susceptibility and with these values we made the phase diagram Tc versus p fordifferent α values. Our results were compared with those obtained using a new technique in effective fieldtheory which employs similar probability distribution within the framework of two-site clusters.

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