RESPONSE OF A STOCHASTIC BISTABLE MODEL-DRIVEN BY STRONG TIME-DEPENDENT FIELDS

The long time response of a bistable stochastic model driven by large amplitude time-dependent sinusoidal fields is investigated by numerica lly solving the Langevin or the Fokker-Planck equation. The noise aver age behavior is oscillatory in time. For a given strength of the drivi ng field, the behavior with the noise of the amplitude and phase of th e fundamental harmonics of the average response depends on the frequen cy. For large driving frequencies, both magnitudes show maxima for two different values of the noise intensity. For a small enough external frequency, those maxima are absent.