Topological colloidal double layers
Charged colloidal suspensions consist of charged micron-sized particles dispersed in a solvent with nanometer-sized ions, and they find ample applications in material science, food industry and drug development. The particle charge, together with a diffuse ion cloud that screens this particle charge, is called the electric double layer and it is pivotal in understanding the phase behaviour and interactions in these suspensions. However, no attention has been paid to the topological properties of the electric double layer. While drawing heavily on recent advances in liquid crystalline systems with topologically non-trivial orientational ordering, we propose to explore the topology of electric double layers, which could ultimately lead to enhanced stability of charged colloidal crystals. Specifically, we will focus on particles with topologically non-trivial shapes and explore the coupling between the topological invariants of the particle (such as genus) with the emergent electric double layer, and how this affects interparticle interactions and the phase behaviour. Finally, the goal of this proposal is to obtain a precise control over charged colloidal suspensions that are protected by topological, rather than only energetic binding, opening a fundamental and applied route to a new class of topological soft matter.