Nonequilibrium Phase Transition in Stochastic Lattice Gases: Simulation of a Three-Dimensional System I

We report results of computer simulations of a three-dimensional lattice gas of interacting particles subject to a uniform external field E. The dynamics of the system is given by hoppings of particles to nearby empty sites with rates biased for jumps in the direction of E. As for the two-dimensional system we find that here too there exists a critical temperature, Tc(E ) such that for T < T~(E) the systems orders in a very anisotropic phase with striplike typical configurations parallel to the field. Tc(E ) increases with E but substantially less strongly than in two dimensions. There is a break in the slope of the saturation current at Tc(E ). Our data are consistent with the critical exponent fl being mean field.