Kinetics in one-dimensional lattice gas and Ising models from time-dependent density-functional theory.

Abstract

Time-dependent density-functional theory, proposed recently in the context of atomic diffusion and nonequilibrium processes in solids, is tested against Monte Carlo simulation. In order to assess the basic approximation of that theory, the representation of nonequilibrium states by a local equilibrium distribution function, we focus on one-dimensional lattice models, where all equilibrium properties can be worked exactly from the known free energy as a functional of the density. This functional determines the thermodynamic driving forces away from equilibrium. In our studies of the interfacial kinetics of atomic hopping and spin relaxation, we find excellent agreement with simulations, suggesting that the method is also useful for treating more complex problems.