Deterministic and stochastic behavior in ferroelectric particles

The response of a ferroelectric particle to an applied harmonic field is studied using the Fokker-Planck equation approach. The size effect in dielectric susceptibility is interpreted as the complementarity between stochastic resonance and response anomaly of the second-order phase transition. The borderline between stochastic and deterministic behavior is established. Two universal volume-independent ratios of the damping rates are predicted and may be verified in the relaxation experiments. The approach can be generalized also to other finite condensed systems.