Dynamical phase diagram of the random field Ising model

Abstract:

The stationary states of the random-field Ising model are determined through the master equation approach, where the contact with the heat bath is simulated by the Glauber stochastic dynamics. The phase diagram of the model is constructed from the stationary values of the magnetization as a function of temperature and field amplitude. The continuous phase transitions coincide with the equilibrium ones, while the first-order transitions occur at fields larger than the corresponding values at equilibrium. The difference between the fields at the limit of stability of the ordered phase and that of the equilibrium is maximum at zero temperature and vanishes at the tricritical point. We also find the mean field time auto-correlation function at the stationary states of the model.