Collective Modes in Two-Dimensional One-Component-Plasma with Logarithmic Interaction

Abstract

Collective modes of a two-dimensional one-component-plasma (2D OCP) with the repulsive logarithmic interaction between the particles are analyzed using the quasi-crystalline approximation (QCA) combined with the molecular dynamic simulation of the equilibrium structural properties. It is found that the dispersion curves in the strongly coupled regime are virtually independent of the coupling strength. Arguments based on the excluded volume consideration for the radial distribution function allow us to derive very simple expressions for the dispersion relations, which show excellent agreement with the exact QCA dispersion over the entire domain of wavelengths.