Dynamic wetting phenomena in lattice models for nematic fluids/liquid crystals near switchable substrate potentials

• Applicant: Professor Dr. Martin Oettel
• Subject Area: Statistical Physics, Nonlinear Dynamics, Complex Systems, Soft and Fluid Matter, Biological Physics
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 422785875

Using theoretical methods and accompanying simulations, we will investigate liquid crystals near switchable substrates. Of particular interest is the approach to wetting transitions and switches between different wetting states.As a model system, we consider lattice rods with short–range attractions. We have developed and will further improve classical density functionals for these models as well as formulate a suitable dynamic density functional theory.Wetting phase diagrams will be computed for nematically ordered (upright or lying–down) and smectic (with possible layering transitions) films. Of particular interest will be the dynamics of smectic layer formation and the switching dynamics between nematic wetting states of different orientation. In these processes, there is little mass transport involved and thus we expect that a lattice dynamics akin to Brownian dynamics can describe these well.Complementary simulations of grand canonical and kinetic Monte Carlo type will be performed to gauge and validate the theoretical results. Through collaborations with experimental groups the results on time–dependence of smectic layering and of the switching between nematic wetting states shall be tested.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2171: Dynamic wetting of flexible, adaptive and switchable surfaces