Vacancy-mediated domain growth in a driven lattice gas

Using Monte Carlo simulations and a mean-field theory, we study domain growth in a driven lattice gas. Mediated by a single vacancy, two species of particles (``charges'') unmix, so that a disordered initial configuration develops charge-segregated domains which grow logarithmically slowly. An order parameter is defined and shown to satisfy dynamic scaling. Its scaling form is computed analytically, in excellent agreement with simulations.