Growth and decay of critical Ising clusters

Z. Alexandrowicz

Jean-Luc Cambier

Michel Pleimling, Ferenc Iglói

We study nonequilibrium dynamical properties at a free surface after the system is quenched from the high-temperature phase into the critical point. We show that if the spatial surface correlations decay sufficiently rapidly the surface magnetization and/or the surface manifold autocorrelations have a qualitatively different universal short time behavior than the same quantities in the bulk. At a free surface cluster dissolution may take place instead of domain growth, yielding stationary dynamical correlations that decay in a stretched exponential form. This phenomenon takes place in the three-dimensional Ising model and should be observable in real ferromagnets.

Jean Christian Anglès d’Auriac, R. Maynard, R. Rammal

László Környei, Michel Pleimling, Ferenc Iglói

We consider nonequilibrium critical dynamics of the two-dimensional Ising model for which the initial state is prepared by switching on random fields with zero mean and variance H . In the initial state there is no magnetic order but the clusters of parallel spins have a percolation transition for small enough H . Using heat-bath dynamics we measure the relaxation of the magnetization which shows a re-entrance in time. Due to cluster dissolution in the early time regime there is a decrease of the magnetization, followed by an increase due to nonequilibrium domain growth which itself turns to a decrease due to equilibrium relaxation. The power law decay of the nonequilibrium autocorrelation function is not influenced by the percolation in the initial state.

Kang K. L. Liu, James Silva, W. Klein +1 more