Possible existence of an extraordinary phase in the driven lattice gas

We report recent simulation results which might indicate the existence of a new low-temperature "phase" in an Ising lattice gas, driven into a non-equ ilibrium steady state by an external field. It appears that this "phase", c haracterized by multiple-strip configurations, is selected when square syst ems are used to approach the thermodynamic limit. We propose a quantitative criterion for the existence of such a "phase". If confirmed, its observati on may resolve a long-standing controversy over the critical properties of the driven Ising lattice gas. (C) 2000 Elsevier Science B.V. All rights res erved.