Cluster-mediated driven transport in highly populated periodic structures

通过密集填充的周期性结构的驱动粒子运动与细胞内过程以及在生物孔、合成通道、胶体单层、微流体装置和固体表面上的运输高度相关。在大颗粒密度，排除体积相互作用占主导地位，颗粒运输涉及合作运动。这些合作运动通常由簇介导，簇是在运动过程中保持在一起的粒子的集合。虽然在最近的实验中可以详细研究集群动力学，但缺乏对它们的良好理论理解。通过结合分析和数值方法，我们的目标是解释集群如何自发地形成在周期性的潜力，即使没有吸引力的相互作用，他们如何移动，以及他们如何可以引起可测量的粒子流在高度拥挤的系统，干扰通常减轻运动。特别强调的是最近发现的布朗动力学中的孤子，它对应于不同类型的集群的周期性运动。我们将探讨孤子在含时周期驱动下的形成和行为，以及周期结构的缺陷和硬核以外的粒子相互作用对孤子运动的影响。在该项目的另一部分，我们将开发新的方法，通过这些方法可以有效地模拟高密度系统中的布朗动力学的基础上集群运动。在与实验组现有合作的基础上，目标集中在易于实验验证的问题上。我们的研究将提供一个全面的理论理解集群介导的驱动运输在各种各样的周期性系统。

Driven particle motion through densely populated periodic structures is of high relevance for intracellular processes as well as transport in biological pores, synthetic channels, colloidal monolayers, microfluidic devices, and on solid surfaces. At large particle densities, excluded volume interactions prevail and particle transport involves cooperative movements. These cooperative movements are often mediated by clusters, which are assemblies of particles that keep together during their motion. While cluster dynamics can be studied in detail in recent experiments, a good theoretical understanding of them is lacking. By combining analytical and numerical methods, our aim is to explain how clusters form spontaneously in periodic potentials even without attractive interaction, how they can move, and how they can give rise to measurable particle currents in highly crowded systems, where jamming typically mitigates motion. Particular emphasis will be given to the recently discovered solitons in Brownian dynamics, which correspond to periodic movements of clusters of different types. It shall be explored how the solitons form and behave under time-dependent periodic driving, and how imperfections in periodic structures and particle interactions beyond hardcore affect soliton motion. In a further part of the project, we will develop new methods by which Brownian dynamics in highly dense systems can be efficiently simulated on the basis of cluster movements. Building on existing cooperations with experimental groups, the objectives are focused on problems amenable to experimental verification. Our studies shall provide a comprehensive theoretical understanding of cluster-mediated driven transport in a large variety of periodic systems.