Equilibrium statistical mechanics for kinetic phase transitions

Dana A. Browne, Louisiana State University
Peter Kleban, Cornell University

Abstract

We consider kinetic models for irreversible processes that exhibit nontrivial steady states and phase transitions between these states. We study the steady states of these nonequilibrium systems using the methods of equilibrium statistical mechanics. To accomplish this, we use two methods for associating an effective Hamiltonian Heff with a given steady state. Varying the kinetic rate parameters changes Heff, which can lead to phase transitions. Since Heff is defined indirectly, the transitions may occur via new mechanisms not possible in equilibrium systems. We apply these methods to several one-dimensional lattice models relevant to certain aspects of catalysis. Two of these models exhibit second-order phase transitions, one to a catalytically inactive state, the other to a catalytically active state. The transitions are in different universality classes. We employ a model used in polymer unbinding and wetting transitions to investigate these transitions. © 1989 The American Physical Society.