Dynamic self-assembly and patterns in electrostatically driven granular media

Phys Rev Lett. 2003 Mar 21;90(11):114301. doi: 10.1103/PhysRevLett.90.114301. Epub 2003 Mar 19.


We show that granular media, consisting of metallic microparticles immersed in a poorly conducting liquid in a strong dc electric field, self-assemble into a rich variety of novel phases. These phases include static precipitates: honeycombs and Wigner crystals; and novel dynamic condensates: toroidal vortices and pulsating rings. The observed structures are explained by the interplay between charged granular gas and electrohydrodynamic convective flows in the liquid.