Stochastic resonance in piecewise potentials

Different characterist es of an output signal (average position, population, average energy) are calculated for a particle moving in a piecewise potential and subject to external periodic and random forces. Particular emphasis has been placed on the dependence of these characteristics on the strength of the noise and the frequency of an external field. An external periodic force strives to equalize the populations of the discrete levels, or even to reverse the populations for the space-extended systems. The populations of the potential wells in a one-barrier system subject to oscillation of the wells can either decrease or increase (compared with the field-free case) dependirg on the frequencies of the external field. All these changes of populations induced by an external field have some resemblance to the similar quantum mechanical problems.