The 'dipole instability' in complex plasmas and its role in plasma crystal melting

Abstract

Using the dipole model for binary dust-dust interactions, the instability of wave perturbations in a one-dimensional particle string oriented along the ion flow (it highlights the major aspect of the multi-layer crystals) is considered. Longitudinal short wavelength perturbations are found to exist below a certain threshold value of gas pressure. They may act as a possible precursor of the melting transition observed in multi-layer plasma crystals. For different discharge conditions, the threshold of this 'dipole instability' is found to be in the range 10-150 Pa. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.