Analysis on the origin of directed current from a class of microscopic chaotic fluctuations

Abstract

An analytical expression of the origin of directed current from a class of microscopic chaotic fluctuations was discussed. The analytical expression was carried out by employing and extending a model by including a generic potential as an additional force field faced by the particle. The results show that the source term gives rise to a directed current for a strongly damped particle in a spatially periodic potential. It was suggested that the in the zeroth-order limit, the position distribution of the particle obeys the Smoluchowski equation even though the fluctuating force is deterministic.