Noise-flatness-induced hypersensitive transport in tilted periodic sawtooth potentials

The noise-flatness-induced hypersensitive transport of overdamped Brownian particles in a tilted periodic sawtooth potential driven by a multiplicative nonequilibrium three-level noise and additive white noise is considered. The study is a follow-up of one of our earlier papers on trichotomous-noise-induced hypersensitive transport [Mankin et al., Phys. Rev. E 68 (2003) 011105]. In the current paper the exact formula for the stationary current is presented. All the physical results discussed are computed by means of the exact formula. It is demonstrated that (i) at low temperatures the enhancement of current is hypersensitive to the applied small static tilting force, (ii) the stationary macroscopic current has a bell-shaped dependence on the parameters, correlation time and flatness, of multiplicative noise which occurs even in the case of large (compared to the ultrasmall DC signal) additive thermal noise, and (iii) at low temperatures and small values of the switching rate, the differential mobility as a function of the tilting force has local minima in a finite range of the force. Implications of the case of multiplicative trichotomous noise are compared with the results of a deterministic square-wave stimulus.