Theory of collision-dominated dust voids in plasmas - art. no. 056609

A dust void, i.e., the dust-free region in a dusty plasma, results from the balance of the electrostatic and plasma (such as the ion drag) forces acti ng on a dust particle. The properties of dust voids depend on the ratio of the void size to the mean free path of plasma ions colliding with neutral s pecies of a weakly ionized plasma. For many plasma-processing and plasma-cr ystal experiments, the size of the void is much larger than the ion-neutral mean free path. The theory and numerical results are presented for such a collisional case including the situations in which the plasma is quasineutr al in the void region or the plasma quasineutrality is violated, as well as the case in which the ion ram pressure is insignificant.