Complex plasmas: forces and dynamical behaviour

Some peculiar features of complex (dusty) plasmas are reviewed and discussed. In the plasma sheath, the supersonic ion flow causes charge accumulation in the ion wake, which leads to attractive forces between like-charged dust particles. Ion drag is an important force under microgravity conditions, where it produces dust-free regions (voids). It is shown that the same mechanism determines dust confinement in anodic plasmas and leads to torus-shaped dust clouds in magnetized plasmas. Spherical plasma crystals are an interesting object of study which have led to an understanding of the influence of shielding on the structure of trapped particle clouds.