Rotating electric fields in complex (dusty) plasmas.

The rotation of monolayer particle clusters suspended in the sheath of a rf discharge plasma was observed experimentally. The cluster rotation was driven by an electric field that rotated uniformly in the horizontal plane (“rotating wall” technique). No external magnetic field was applied. The cluster rotation velocity depended nonmonotonically on the manipulation field frequency that was much higher than the dust plasma frequency. Mechanisms of rotation are proposed based on the interplay between the electric and ion-drag forces. Possible applications of rotating electric fields in complex plasmas are discussed. [ABSTRACT FROM AUTHOR]