Griffiths phase and critical behavior of the 2D Potts models with long-range correlated disorder

Christophe Chatelain (1)

1 IJL - Institut Jean Lamour

The $q$-state Potts model with a long-range correlated disorder is studied by means of large-scale Monte Carlo simulations for $q=2,4,8$ and 16. Evidence is given of the existence of a Griffiths phase, where the thermodynamic quantities display an algebraic Finite-Size Scaling, in a finite range of temperatures around the self-dual point. The critical exponents are shown to depend on both the temperature and the exponent of the algebraic decay of disorder correlations, but not on the number of states of the Potts model. The mechanism leading to the violation of hyperscaling relations is observed in the entire Griffiths phase.

Mots clés: Potts model; Ashkin-Teller model; correlated disorder; Monte Carlo simulations; Griffiths phase; hyperscaling violation

Domaines: Mécanique statistique [cond-mat.stat-mech]

Christophe Chatelain. Griffiths phase and critical behavior of the 2D Potts models with long-range correlated disorder. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2014, 89, pp.032105. ⟨10.1103/PhysRevE.89.032105⟩. ⟨hal-00850126v2⟩