论文标题
布朗粒子在平衡和非平衡中的扩散系数：爱因斯坦模型及以后
Diffusion coefficient of a Brownian particle in equilibrium and nonequilibrium: Einstein model and beyond
论文作者
论文摘要
在自然界中发生的大量过程中，小颗粒的扩散无处不在。因此，它在几乎所有科学的分支中都进行了广泛的研究和施加。它构成了如此广泛且通常相当复杂的探索主题，我们选择在这里缩小对布朗粒子扩散系数的调查，该粒子可以在Langevin Dynamics的框架中建模。我们的主要重点将集中在几种不同物理系统基本模型的扩散系数的温度依赖性上。从平衡的扩散开始，爱因斯坦理论认为，我们考虑了从自由布朗运动的许多物理情况，最终测量了在周期性电位中随机居住的时间周期驱动的布朗粒子，以测量非平衡扩散。在后一种情况下，扩散系数表现出对温度的有趣的非单调依赖性。
Diffusion of small particles is omnipresent in a plentiful number of processes occurring in Nature. As such, it is widely studied and exerted in almost all branches of sciences. It constitutes such a broad and often rather complex subject of exploration that we opt here to narrow down our survey for the case of the diffusion coefficient for a Brownian particle which can be modeled in the framework of Langevin dynamics. Our main focus will center on the temperature dependence of the diffusion coefficient for several fundamental models of diverse physical systems. Starting out with diffusion in equilibrium for which the Einstein theory holds we consider a number of physical situations away from free Brownian motion and end with surveying nonequilibrium diffusion for a time-periodically driven Brownian particle dwelling randomly in a periodic potential. For this latter situation the diffusion coefficient exhibits an intriguingly non-monotonic dependence on temperature.
