Actively spinning particles attracted much attention in recent years, mostly from a point of view of their ability to self-assemble on the liquid surface. On the other hand, the control of surface flows using surface waves has led to interesting analogies with optical traps for microparticles and ultracold atoms. In this talk I will present recent experiments on the confinement of active spinners within a wave-driven vortex lattice, also referred to as liquid metamaterial. I will discuss properties of the surface flow generated by two orthogonal standing waves. The spinners can be efficiently manipulated in such a flow to either occupy stationary orbits within a metamaterial cell, or they can be moved between the cells. I will discuss forces acting on the spinners in such flows and will show how multiple spinners interact to form stable self-organised configurations.
ICTP - Strada Costiera, 11
I - 34151 Trieste Italy (+39) 040 2240 111 firstname.lastname@example.org