Theory of correlation effects in dusty plasmas

A theory of correlation effects in dusty plasmas based on a suitably augmented Debye Huckel approximation is proposed. A model which takes into account the confinement of the dust within the plasma (by external fields) is considered. The dispersion relation of compressional modes with correlation effects is obtained. Results show that strong coupling effects may be subdominant even when Gamma >> 1. Thus, in the limit Gamma -> 0 and/or kappa -> infinity, one obtains the weakly coupled dust thermal mode. In the range of values of Gamma >> 1, the strong coupling effects scale with kappa instead of Gamma; increasing Gamma increases the dust acoustic waves phase velocity C-DAW in this regime. In the limit Gamma >> 1; kappa << 1, one obtains the weakly coupled dust acoustic wave. Only in the limit Gamma >> 1; kappa >= 1, one obtains strong coupling effects, e. g., the dust lattice waves (kappa = a/lambda(d), a is the mean particle distance and lambda(d) is the Debye length). Observations from a number of experiments are explained. (C) 2015 AIP Publishing LLC.