Reciprocating nanoengine

Abstract

Brownian motion in a confining potential fluctuating between two spatially separated potential profiles is considered as a model of an engine converting nonequilibrium fluctuations into reciprocating motion on the nanoscale. We present two exact solutions obtained for the parabolic and step potential, which reveal the temperature and frequency-modulation behavior of the engine. The confining potential determines the interplay of the independent internal (thermal) and external (discrete) noises: the noises are cooperated for any potential, except the parabolic one. The engine can operate as a molecular motor, being supplemented by a rectifying mechanism.