On the Effect of Confinement on the Structure of a Complex (Dusty) Plasma

Abstract

The influence of the confining parabolic potential (confinement) on the equilibrium configurations of a bounded highly nonideal complex (dusty) plasma in the one- and two-dimensional cases in the approximation of the pair interaction between microparticles by means of the Yukawa potential has been considered. In particular, it has been shown that the dust component of the complex plasma is essentially inhomogeneous in such a confining potential: the density of microparticles drops markedly to the system boundaries. This effect qualitatively changes the character of phase transitions (melting and crystallization) in such systems. For example, melting (crystallization) of a two-dimensional system of microparticles occurs with the formation of a melting (crystallization) wave, which propagates from the boundaries of the system to its center (in the case of crystallization, it propagates from the center to the boundaries). It has been shown that the equilibrium distribution of the density of the microparticles is determined only by the stiffness of the interparticle interaction, which makes it possible to noninvasively determine the screening parameter κ, which is the key interaction parameter, in the experiments with dusty plasma.