物理学报Issue(9)：1-8,8.DOI:10.7498/aps.64.090505
时间非对称外力驱动分数阶布朗马达的定向输运∗
Directed transp ort of fractional Brownian motor driven by a temp oral asymmetry force
摘要
Abstract
The directed transport of a Brownian particle in a spatially periodic symmetric field under a temporal asymmetric force is studied. Based on the Caputo’s fractional derivatives theory, we establish a differential aquation for an over-damped fractional Brownian motor as the system’s mathematic model, where the external force is zero-mean and the fractional order is used to describe the inhomogeneity of the real environment. Using the fractional differential algo-rithm, we analyze the relationships between transport velocity and model parameters. It is worth mentioning that the impact of fractional order is discussed in detail. According to the research we find that a temporal asymmetric force can induce a net current without the application of a ratchet potential, even a noise. We also find that the velocity of the current increases monotonically with the increase in fractional order. Moreover with certain fractional orders, a generalized resonance phenomenon is revealed since the velocity of the current varies non-monotonically with the system parameters, such as the height of the potential barrier and the noise strength etc. Research shows that the fractional system is a generalization of the traditional dynamic systems, which could probably give a more reasonable explanation of the directed transport as a consequence.关键词
定向输运/布朗马达/分数阶郎之万方程/广义随机共振Key words
directed transport/Brownian motor/fractional Langevin equation/generalized stochastic resonance引用本文复制引用
任芮彬,刘德浩,王传毅,罗懋康..时间非对称外力驱动分数阶布朗马达的定向输运∗[J].物理学报,2015,(9):1-8,8.基金项目
国家自然科学基金(批准号:11171238)和电子信息控制重点实验室项目(批准号:2013035)资助的课题.* Project supported by the National Natural Science Foundation of China (Grant No.11171238), and the Science and Technology on Electronic Information Control Laboratory Program (Grant No.2013035) （批准号:11171238）
