Steering the potential barriers: entropic to energetic.
Steering the potential barriers: entropic to energetic.
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DOI：
10.1103/physreve.82.051128
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发表时间：
2010-10
期刊：
影响因子：
--
通讯作者：
P. S. Burada;G. Schmid
中科院分区：
文献类型：
--
作者：
P. S. Burada;G. Schmid
我们提出了一种机制，当一个有偏压的布朗粒子在狭窄的周期性通道中进行约束运动时，可以改变势垒的性质。通过改变外偏压的角度，势垒的性质从纯熵变为能量，这反过来又影响系统中的扩散过程。在最佳偏置角下，非线性迁移率呈现出明显的钟形行为。此外，缩放的有效扩散系数的增强可以通过偏置的角度有效地控制。这种机制使得能够正确设计用于分子和小颗粒传输的通道结构。精确的布朗动力学模拟验证了近似的解析预测。
We propose a mechanism to alter the nature of the potential barriers when a biased brownian particle undergoes a constrained motion in narrow periodic channel. By changing the angle of the external bias, the nature of the potential barriers changes from purely entropic to energetic, which in turn affects the diffusion process in the system. At an optimum angle of the bias, the nonlinear mobility exhibits a striking bell-shaped behavior. Moreover, the enhancement of the scaled effective diffusion coefficient can be efficiently controlled by the angle of the bias. This mechanism enables the proper design of channel structures for transport of molecules and small particles. The approximate analytical predictions have been verified by precise brownian dynamics simulations.