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.
- Absorbing state,
- Contact process,
- Equilibrium systems,
- Macroscopic state,
- Monte Carlo Simulation,
- Nonequilibrium phase transitions,
- Random fields,
- Spontaneous symmetry breaking,
- Atomic physics,
- Physics
Available at: http://works.bepress.com/thomas-vojta/121/