Stoke's efficiency of temporally rocked ratchets

TL;DR

This paper analyzes the efficiency of adiabatically rocked ratchets with asymmetry, deriving an analytical expression and showing how parameter tuning can optimize generalized efficiency, which is distinct from thermodynamic efficiency.

Contribution

It provides an analytical expression for the generalized efficiency of rocked ratchets and explores how parameter tuning affects efficiency, highlighting differences from thermodynamic efficiency.

Findings

Generalized efficiency can reach about 50% with parameter tuning.

Higher generalized efficiency is due to suppression of backward current.

Temperature optimizes generalized efficiency across parameters.

Abstract

We study the generalized efficiency of an adiabatically rocked ratchet with both spatial and temporal asymmetry. We obtain an analytical expression for the generalized efficiency in the deterministic case. Generalized efficiency of the order of 50% is obtained by fine tuning of the parameter range. This is unlike the case of thermodynamic efficiency where we could readily get an enhanced efficiency of upto 90%. The observed higher values of generalized efficiency is attributed to be due to the suppression of backward current. We have also discussed briefly the differences between thermodynamic, rectification or generalized efficiency and Stoke's efficiency. Temperature is found to optimize the generalized efficiency over a wide range of parameter space unlike in the case of thermodynamic efficiency.