Critical Behavior of the Two-Dimensional Randomly Driven Lattice Gas

Abstract

We investigate the critical behavior of the two-dimensional randomly driven lattice gas, in which particles are driven along one of the lattice axes by an infinite external field with randomly changing sign. A finite-size scaling (FSS) analysis provides novel evidences that this model is not in the same universality class as the driven lattice gas with a constant drive (DLG), contrarily to what has been recently reported in the literature. Indeed, the FSS functions of transverse observables (i.e., related to order-parameter fluctuations with wave vector perpendicular to the direction of the field) differ from the mean-field behavior predicted and observed within the DLG universality class. At variance with the DLG case, FSS is attained on lattices with fixed aspect ratio and anisotropy exponent equal to 1 and the transverse Binder cumulant does not vanish at the critical point.