Transport properties of quasi-two-dimensional dissipative systems with a screened Coulomb potential
- PDF / 339,722 Bytes
- 9 Pages / 612 x 792 pts (letter) Page_size
- 0 Downloads / 137 Views
EAL PLASMA
Transport Properties of Quasi-Two-Dimensional Dissipative Systems with a Screened Coulomb Potential O. S. Vaulina and I. E. Dranzhevskiœ Institute for High Energy Densities, Russian Academy of Sciences, Izhorskaya ul. 13/19, Moscow, 125412 Russia Received June 30, 2006; in final form, November 9, 2006
Abstract—Results are presented from numerical investigations of the dynamics of quasi-two-dimensional systems in the form of a monolayer of dust grains interacting by means of a screened Coulomb potential and suspended in the Earth’s gravitational field by an external electric field. The structural and transport characteristics of such a system, including the pair correlation functions and the viscosity and diffusion coefficients, were investigated over a broad parameter range corresponding to the conditions under which dust structures are observed in RF capacitive discharge plasmas. An analysis of the results obtained revealed that there is a specific topological transition typical of systems having a low spatial dimension. PACS numbers: 52.27.Lw, 52.27.Gr DOI: 10.1134/S1063780X07060062
1. INTRODUCTION Investigations of the transport properties of dissipative systems of interacting particles are of great interest for various fields of science and technology (in particular, hydrodynamics, plasma physics, physics of polymers, etc.) [1–5]. The main problem in studying the physical features of such systems is that there is no analytic theory of liquids that can explain their thermodynamic properties, describe the heat and mass transfer phenomena, and so on. Two main approaches exist to develop the theory of strongly nonideal systems, as well as approximate models for describing the liquid state of matter. The first approach is based on the fullscale statistical calculation of the properties of nonideal media by the molecular dynamics method with the use of model data on the interparticle interaction energy [6– 19]. The second approach (the so-called theory of “jumps”) is a semi-empirical method based on the analogy between crystalline and liquid states of matter [1– 4]. A dusty plasma consisting of electrons, ions, buffer gas atoms, and micron-size dust grains (macroparticles) provides a good experimental model for studying the properties of strongly nonideal plasmas and for checking the models used in the theory of liquids. The dust grains in plasmas are large enough to be recorded by a video camera, so their dynamics can be studied at the kinetic level [18–26]. The properties of dusty plasma are investigated mostly in experiments with weakly ionized gas-discharge plasmas, in which dissipation due to collisions of dust grains with neutral gas particles plays a significant role. In such a plasma, nonemitting dust grains can acquire a substantial negative charge, |eZ | ~ 102–105e, and can form three-dimensional (3D) or quasi-two-dimensional (quasi-2D) liquid- or
solid-like structures. The formation of quasi-2D structures consisting of several (from one to ten) dust layers is typically observed in experiments
Data Loading...
