Dynamic, self-assembled aggregates of magnetized, millimeter-sized objectsrotating at the liquid-air interface: Macroscopic, two-dimensional classical artificial atoms and molecules - art. no. 011603

This paper describes self-assembly of millimeter-sized, magnetized disks fl oating on a liquid-air interface. and rotating under the influence of a rot ating external magnetic field. Spinning of the disks results in hydrodynami c repulsion between them, while the rotating magnetic held produces an aver age confining potential acting on all disks. The interplay between hydrodyn amic and magnetic interactions leads to the formation of patterns. Theoreti cal analysis of hydrodynamic and magnetic forces indicates that the interac tions in this system are similar to those acting in systems of finite numbe rs of particles behaving classically ("classical artificial atoms"). Macros copic artificial atoms and molecules are described, and the rules governing their morphologies outlined.