Collective and tracer dynamics in single-file transport through periodic structures

单列传输是指在多粒子系统中，由于粒子间的相互作用和空间限制，粒子之间不能相互超越。本文研究了具有单列特征的扩散主体的随机布朗运动。这种类型的运动在自然界和技术中普遍存在，每当颗粒被迫通过直径仅略大于颗粒尺寸的狭窄孔隙时。突出的例子是在结晶铝硅酸盐（沸石），膜通道，纳米管，通道中的微和纳米流体设备，以及胶体运动在实验中与先进的光学和磁性操纵技术的扩散。虽然这些和其他的例子通常涉及周期性结构，理论工作主要集中在空间均匀的系统相对于一个单一的标记粒子（示踪剂）的异常subdiffusion，或onoversimplified离散系统相对于collective transportproperties。对通过周期结构的单列布朗运动中的示踪剂和集体动力学的理解仍然缺失。在这个双边项目中，我们的目标是通过开发范式模型和分析方法来填补这一空白。这包括分析方法和有效的模拟技术。我们的具体目标是发展一个完整的硬球粒子行为理论，这将作为进一步研究其他类型的短程粒子相互作用和具有不同类型粒子的系统的基础。我们将特别强调通过观察示踪剂在周期性结构中的位置之间的跃迁动力学来探测集体行为的不同阶段的可能性。结果sobtained为理想化的一维单行传输将becheck相对于其有效性为相应的full-three-dimensional孔隙结构。

Single-file transport refers to the motion in a many-particle system,where the particles cannot overtake each other because of theirinteractions and spatial confinements. In this project the stochasticBrownian motion of diffusion agents with single-file character isconsidered. This type of motion occurs ubiquitously in nature andtechnology whenever particles are forced to move through narrow poreswith diameters only slightly larger than the particle size. Prominentexamples are diffusion in crystalline aluminosilicates (zeolites),membrane channels, nanotubes, channels in micro- and nanofluidicdevices, as well as colloid motions in experiments with advancedoptical and magnetic manipulation techniques. While these and otherexamples typically involve periodic structures, theoretical work hasmainly focused so far on spatially homogeneous systems with respect tothe anomalous subdiffusion of a single tagged particle (tracer), or onoversimplified discrete systems with respect to collective transportproperties. An understanding of tracer and collective dynamics insingle-file Brownian motion through periodic structures is stillmissing. In this bilateral project, we aim to fill this gap bydeveloping paradigmatic models and methods for their analysis. Thisincludes both analytical approaches and efficient simulationtechniques. Our specific objectives are to develop a full theory forparticles behaving like hard spheres, which will serve as a basis forfurther investigations of other types of short-range particleinteractions and systems with different types of particles.Particular emphasis will be put on the possibility to probe differentphases of collective behavior by observing a tracer's transitionkinetics between sites in the periodic structures. Resultsobtained for idealized one-dimensional single-file transport will bechecked with respect to their validity for corresponding fullthree-dimensional pore structures.