Laboratoire Matière et Systèmes Complexes

Liquid crystals are complex fluids with partially crystalline characteristics. They can have orientational/translational order but they can flow like fluids. Bringin a second component into the system, for example a colloidal particles (e.g. micrometer length scale spheres), leads to deformations of the liquid crystalline order near the surface(s). In the case of colloids, this creates elastic interactions between the particles.

In this talk, I will describe our recent hydrodynamic simulation efforts on understanding the LC composite systems. The results include strong structural rigidity observed in nematic/colloid composites stemming from particle stabilised defect networks percolating in 3D and multistable switchable structures created when the colloidal particles are mixed with a chiral liquid crystal.

I will then expand the system include two phase separating fluids (isotropic fluid and LC) and describe a templated self-assembly of particles trapped on an interface between chiral liquid crystal and silicone oil. Finally, I will discuss ongoing research on very chiral liquid crystal emulsions. Under certain conditions, the behaviour of the coarsening isotropic fluid droplets is similar to what is observed with solid particles. I will then show that when the interfacial tension between these two fluids is reduced, the liquid crystalline elasticity dominates the behaviour, leading to stable emulsions with a cubic symmetry.