分子尺度不对称体系中热噪声引发的单向输运  

Biased transportation in molecular-scale asymmetric systems induced by thermal noise

作　　者：孔令伟[1,2] 万荣正[1] 方海平[1] 

机构地区：[1]中国科学院上海应用物理研究所,上海201800 [2]中国科学院大学,北京100080

出　　处：《物理》2014年第7期446-452,共7页Physics

基　　金：国家自然科学基金(批准号:11175230)资助项目

摘　　要：不对称体系中的单向输运现象广泛存在于自然界中,宏观理论认为,体系的空间反演不对称性和有一定自相关时间的外加振动是引发单向运动的两个必要条件,因而一般认为,在分子尺度的不对称体系中,仅有热噪声也还是不会引发单向运动的。随着实验技术和计算手段的发展,有迹象表明,在分子尺度的不对称体系中,即使没有外加振动也会有单向运动产生。文章介绍在分子尺度由体系热噪声引发的不对称体系中,单向输运的理论进展,以及产生这种单向输运的条件。Biased transportation in asymmetric systems widely exist in nature. The mac-ro-scale theory indicates that breaking of the spatial inversion symmetry and external fluctuations with a certain auto-correlation time are two requirements for biased transportation. Thus, it is gen-erally believed that thermal noise alone cannot induce biased transportation in molecular-scale asymmetric systems. With the development of experimental technology and simulation methods, biased transportation has been observed in these systems even without external fluctuations. This article describes some recent theoretical research on biased transportation induced by thermal noise in molecular-scale asymmetric systems, and the necessary conditions.

关 键 词：棘轮 朗之万方程 热噪声 自相关时间 

分 类 号：O552[理学—热学与物质分子运动论]