Current Reversals and Synchronization in Coupled Ratchets

TL;DR

This paper investigates how coupling two ratchets influences current reversal phenomena, revealing that coupling can eliminate reversals and optimize transport at specific parameters.

Contribution

It demonstrates that coupling in a two-ratchet system can control current reversals and identify conditions for optimal transport.

Findings

Coupling can eliminate current reversals in ratchet systems.

A regime without current reversal exists at specific coupling strengths.

Optimal transport occurs at a particular driving amplitude in synchronized states.

Abstract

Current reversal is an intriguing phenomenon that has been central to recent experimental and theoretical investigations of transport based on ratchet mechanism. By considering a system of two interacting ratchets, we demonstrate how the coupling can be used to control the reversals. In particular, we find that current reversal that exists in a single driven ratchet system can ultimately be eliminated with the presence of a second ratchet. For specific coupling strengths a current-reversal free regime has been detected. Furthermore, in the fully synchronized state characterized by the coupling threshold $k_{th}$, a specific driving amplitude $a_{opt}$ is found for which the transport is optimum.