Fluctuation-driven directed transport in the presence of Levy flights

TL;DR

This paper demonstrates that symmetric Levy noise can induce directed transport in ratchet potentials without external tilting, with the current optimized at specific Levy noise parameters and controllable via noise and potential asymmetries.

Contribution

It provides numerical evidence that Levy noise can drive directed transport in ratchet systems, highlighting the role of Levy noise parameters and asymmetries in controlling current.

Findings

Levy noise induces net current in ratchet potentials.

Optimal Levy noise index maximizes current.

Current direction and magnitude are controllable via asymmetries.

Abstract

Numerical evidence of directed transport driven by symmetric Levy noise in time-independent ratchet potentials in the absence of an external tilting force is presented. The results are based on the numerical solution of the fractional Fokker-Planck equation in a periodic potential and the corresponding Langevin equation with Levy noise. The Levy noise drives the system out of thermodynamic equilibrium and an up-hill net current is generated. For small values of the noise intensity there is an optimal value of the Levy noise index yielding the maximum current. The direction and magnitude of the current can be manipulated by changing the Levy noise asymmetry and the potential asymmetry.