We study 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 show that the phase transition of the one-dimensional generalized contact process persists in the presence of random-field disorder. The ultraslow dynamics in the symmetry-broken phase 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 large-scale Monte Carlo simulations.
H. Barghathi and T. Vojta, "Random Fields at a Nonequilibrium Phase Transition," Physical Review Letters, vol. 109, no. 17, pp. 170603-1 - 170603-5, American Physical Society (APS), Oct 2012.
The definitive version is available at https://doi.org/10.1103/PhysRevLett.109.170603
Keywords and Phrases
Absorbing state; Contact process; Equilibrium systems; Macroscopic state; Monte Carlo Simulation; Nonequilibrium phase transitions; Random fields; Spontaneous symmetry breaking; Atomic physics; Physics
International Standard Serial Number (ISSN)
Article - Journal
© 2012 American Physical Society (APS), All rights reserved.
01 Oct 2012