3 research outputs found
Non-equilibrium relaxation and critical aging for driven Ising lattice gases
We employ Monte Carlo simulations to study the non-equilibrium relaxation of
driven Ising lattice gases in two dimensions. Whereas the temporal scaling of
the density auto-correlation function in the non-equilibrium steady state does
not allow a precise measurement of the critical exponents, these can be
accurately determined from the aging scaling of the two-time auto-correlations
and the order parameter evolution following a quench to the critical point. We
obtain excellent agreement with renormalization group predictions based on the
standard Langevin representation of driven Ising lattice gases.Comment: 5 pages, 4 figures included; to appear in Phys. Rev. Lett. (2012
Slow relaxation and aging kinetics for the driven lattice gas
We numerically investigate the long-time behavior of the density-density
auto-correlation function in driven lattice gases with particle exclusion and
periodic boundary conditions in one, two, and three dimensions using precise
Monte Carlo simulations. In the one-dimensional asymmetric exclusion process on
a ring with half the lattice sites occupied, we find that correlations induce
extremely slow relaxation to the asymptotic power law decay. We compare the
crossover functions obtained from our simulations with various analytic results
in the literature, and analyze the characteristic oscillations that occur in
finite systems away from half-filling. As expected, in three dimensions
correlations are weak and consequently the mean-field description is adequate.
We also investigate the relaxation towards the nonequilibrium steady state in
the two-time density-density auto-correlations, starting from strongly
correlated initial conditions. We obtain simple aging scaling behavior in one,
two, and three dimensions, with the expected power laws.Comment: 12 pages, 18 figures; to appear in Phys. Rev. E (2011