Ai Bao-Quan, Wang Xian-Ju, Liu Guo-Tao, Wen De-Hua, Xie Hui-Zhang, Chen Wei, Liu Liang-Gang
Department of Physics, ZhongShan University, GuangZhou, China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2003 Dec;68(6 Pt 1):061105. doi: 10.1103/PhysRevE.68.061105. Epub 2003 Dec 24.
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.
研究了在存在不对称无偏涨落的情况下，布朗粒子在周期势场中运动的效率。我们发现，即使在准静态极限下，也存在一个效率可以是温度的峰值函数的区域，这证明了热涨落促进了能量转换效率，这与早期的研究结果[H. Kamegawa等人，《物理评论快报》80, 5251 (1998)]相矛盾。还发现时间不对称和空间不对称之间的相互作用可能会在有限温度下诱导出优化的效率。棘轮在给出最大电流时并非效率最高。
