Systems driven out of equilibrium by an external field such as temperature gradient or electric field, often reach a steady state which supports currents. These steady states are very different from thermal equilibrium states. In particular they tend to exhibit long-range correlations which may sometime result in phase transitions and long-range order in one dimension.
Our group is engaged in theoretical studies of the nature of non-equilibrium steady states and their dynamics by analyzing prototypical models introduced for this purpose.