Abstract
S. Klapp: „Soft Matter between two and three dimensions: "Simple" effects and the impact of additional fields”
TU Berlin
The physics of fluids confined in pores or slits can be strongly different from that observed in three spatial dimensions. In this talk I will present recent computer simulation and theoretical results on spatially confined colloidal systems. A well-known surface effect consists of a layering of the particles which can be detected, e.g., by oscillations in the solvation forces. However, the length scales determining such forces are still under debate. Here I will discuss these issues for a film of charged colloids, including an interpretation via density functional theory and a comparison with experimental (Colloidal-Probe AFM) data. I also show how the confinement affects the freezing transition in the charged system. Even more complex layering effects occur when the spatial confinement is supplemented by additional external fields. In particular, in films with dipolar interactions such as ferrofluids, external magnetic fields can give rise to layer formation, layer destruction, and field-induced crystallization.