Ai Bao-Quan, Xie Hui-Zhang, Liu Liang-Gang
Institute for Condensed Matter Physics, School of Physics and Telecommunication Engineering and Laboratory of Photonic Information Technology, South China Normal University, 510006 Guangzhou, China.
Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Jun;75(6 Pt 1):061126. doi: 10.1103/PhysRevE.75.061126. Epub 2007 Jun 28.
Efficiency of a Brownian particle moving along the axis of a three-dimensional asymmetric periodic channel is investigated in the presence of a symmetric unbiased force and a load. Reduction of the spatial dimensionality from two or three physical dimensions to an effective one-dimensional system entails the appearance of entropic barriers and an effective diffusion coefficient. The energetics in the presence of entropic barriers exhibits peculiar behavior which is different from that occurring through energy barriers. We found that even on the quasistatic limit there is a regime where the efficiency can be a peaked function of temperature, which indicates that thermal noise can facilitate energy transformation, contrary to the case of energy barriers. The appearance of entropic barriers may induce optimized efficiency at a finite temperature.
研究了在存在对称无偏力和负载的情况下，沿三维非对称周期性通道轴移动的布朗粒子的效率。将空间维度从两个或三个物理维度降低到有效的一维系统会导致熵垒的出现和有效扩散系数。存在熵垒时的能量学表现出与通过能垒出现的行为不同的特殊行为。我们发现，即使在准静态极限下，也存在一种情况，即效率可以是温度的峰值函数，这表明热噪声可以促进能量转换，这与能垒的情况相反。熵垒的出现可能会在有限温度下诱导出优化效率。
