Emergent self-propulsion at low Reynolds number

We here demonstrate the experimental realization of inanimate micro-swimmer complexes showing emergent self-propulsion at low Reynolds number Re < 10^(-4) in quasi 2D colloidal systems. Guided by the substrate, self-organized propulsion occurs for up to 25min with typical velocities of 1-3 \mu m/s, while none of the involved constituents shows self-propulsion on its own.