physica status solidi (b)
Dynamic Response of an Ising System to a Time-Dependent Field
T. Pitzschke, Steffen Trimper
Abstract
The basic equation of a kinetic Ising model under the influence of a time dependent field is rederived applying the Fock space representation of the master equation. The nonequilibrium behaviour of the model in the presence of both a static and an oscillating magnetic field is analyzed by numerical simulations and by scaling arguments. Forcing the system to be initially in the metastable state and imposing an additional oscillating field makes it possible to study the relaxation time of this state. We find a power law behaviour for the waiting time depending on the amplitude and the frequency of the field as well as on the reduced temperature. The critical exponents are determined numerically. Furthermore, the results are supported by scaling arguments.