Random fields at a nonequilibrium phase transition

Hatem Barghathi; Thomas Vojta

doi:10.1103/physrevlett.109.170603

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arXiv · 1206.1878

Random fields at a nonequilibrium phase transition

Hatem Barghathi·Thomas Vojta

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Abstract

We investigate nonequilibrium phase transitions in the presence of disorder that locally breaks the symmetry between two equivalent macroscopic states. In low-dimensional equilibrium systems, such "random-field" disorder is known to have dramatic effects: It prevents spontaneous symmetry breaking and completely destroys the phase transition. In contrast, we demonstrate that the phase transition of the one-dimensional generalized contact process persists in the presence of random field disorder. The dynamics in the symmetry-broken phase becomes ultraslow and is described by a Sinai walk of the domain walls between two different absorbing states. We discuss the generality and limitations of our theory, and we illustrate our results by means of large-scale Monte-Carlo simulations.

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Hatem Barghathi, Thomas Vojta. 2012-10-29. Random fields at a nonequilibrium phase transition. https://doi.org/10.1103/physrevlett.109.170603

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