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Reentrance during nonequilibrium relaxation

Laszlo Kornyei·Michel Pleimling·Ferenc Igloi
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Abstract

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 heath-bath dynamics we measure the relaxation of the magnetization which shows a reentrance 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.

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Laszlo Kornyei, Michel Pleimling, Ferenc Igloi. 2005-09-14. Reentrance during nonequilibrium relaxation. https://doi.org/10.1209/epl%2Fi2005-10386-5

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