Dynamic circulation in a complex plasma

Abstract

The dynamic circulation of dust particles in a cylindrical complex plasma is studied experimentally. A levitated cloud of charged dust particles rotates around an axis in an ion flow induced by the coupling of applied magnetic field with the electric field due to plasma density gradient. The vertical and horizontal cross sections of the cloud reveal the dynamic circulation with helical trajectories of dust particles with meridional ascending motion near the axis. The dust particles in the center bottom in the cloud remain near a stagnation point and act like tea leaves in a teacup as described by Einstein in 1926.