title: Efficiency optimization in a correlation ratchet with asymmetric unbiased fluctuations.
abstract: The efficiency of a Brownian particle moving in a periodic potential in the presence of asymmetric unbiased fluctuations is investigated. We found that even on the quasistatic limit there is a regime where the efficiency can be a peaked function of temperature, which proves that thermal fluctuations facilitate the efficiency of energy transformation, contradicting the earlier findings [H. Kamegawa et al., Phys. Rev. Lett. 80, 5251 (1998)]. It is also found that the mutual interplay between temporal asymmetry and spatial asymmetry may induce optimized efficiency at finite temperatures. The ratchet is not most efficient when it gives maximum current.
authors.affiliation: Department of Physics, ZhongShan University, GuangZhou, China.
authors.forename: Bao-Quan
authors.initials: BQ
authors.lastname: Ai
authors.forename: Xian-Ju
authors.initials: XJ
authors.lastname: Wang
authors.forename: Guo-Tao
authors.initials: GT
authors.lastname: Liu
authors.forename: De-Hua
authors.initials: DH
authors.lastname: Wen
authors.forename: Hui-Zhang
authors.initials: HZ
authors.lastname: Xie
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Liang-Gang
authors.initials: LG
authors.lastname: Liu