Study of the Critical Behavior of the Driven Lattice Gas Model with Limited Nonequilibrium Dynamics

G. P. SARACCO; M. L. RUBIO PUZZO; M. A. BAB

Buenos Aires

Simposio; Frontiers in Physical Sciences; 2016

International Center for Advanced Studies(ICAS) y Max Planck Liason Office for Latin America

In this paper the nonequilibrium critical behavior is investigated using a variant of the well-known two-dimensional driven lattice gas (DLG) model, called modified driven lattice gas (MDLG). In this model, the application of the external field is regulated by a parameter p [0, 1] in such a way that if p = 0, the field is not applied, and it becomes the Ising model, while if p = 1, the DLG model is recovered.The behavior of the model is investigated for several values of p by studying the dynamic evolution of the system within the short-time regime in the neighborhood of a phase transition. It is found that the system experiments second-order phase transitions in all the interval of p for the density of particles \rho = 0.5. The determined critical temperatures Tc(p) are greater than the critical temperature of the Ising model TcI, and increase with p up to the critical temperature of the DLG model in the limit of infinite driving fields. The dependece of Tc(p) on p is compatible with a power-law behavior whose exponent is \phi= 0.27(3).Furthermore, the complete set of the critical and the anisotropic exponents is estimated. For the smallest value of p, the dynamic and exponents are close to that calculated for the Ising model, and the anisotropic exponent is near zero. As p is increased, the exponents and change, meaning that the anisotropy effects increase. For the largest value investigated, the set of exponents approaches to that reported by the most recent theoretical framework developed for the DLG model.