From Chaos to Order: Evaporative Assembly and Collective Behavior in Drying Liquid Crystal Droplets

The emergence of dynamic assembly and collective motion in living systems are marvels of nature that suggest universal principles for governing self-organization. By drying a drop of surfactant-stabilized liquid crystal emulsions, we present a simple form of evaporative assembly and collective motion in colloidal droplets. Driven by local evaporation flux distribution and capillary force, the dynamic mode in these swimming liquid crystal droplets highly depends on their intrinsic configurations, exhibiting a macroscopic transition from chaotic to well-organized. The combination of collective behavior, speed distribution, interparticle interaction, formation of topological defects and dislocations in a swarm of hexagonal ordered liquid crystal droplets produced a myriad of dynamical states, which suggest a means of mimicking the nonequilibrium state of living matter with controlled properties.