Wake effects on vertical alignment of two dust particles in a rf plasma sheath

Abstract

A theoretical method is proposed to study the motion of two dust particles in a radio-frequency plasma sheath with flowing ions. It is shown that, owing to the asymmetric wake force, the particles move in a coordinated way, remaining aligned in a direction perpendicular to an electrode, when a modulating laser beam hits the upper particle. These results imply that the wake effects may be responsible for formation of the vertically aligned Coulomb crystal structure.