Cluster-mediated driven transport in highly populated periodic structures

• Applicant: Professor Dr. Philipp Maass
• Subject Area: Statistical Physics, Nonlinear Dynamics, Complex Systems, Soft and Fluid Matter, Biological Physics
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 521001072

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.

• DFG Programme: Research Grants
• International Connection: Czech Republic
• Partner Organisation: Czech Science Foundation
• Cooperation Partner: Artem Ryabov, Ph.D.