Electrostatic Dust Modes in Non-Ideal Dusty Plasmas with Grain Charge Fluctuations

Abstract

The linear as well as the nonlinear propagation of dust–acoustic waves (DAWs), dust–charge–density waves (DCDWs) and dust–coulomb waves (DCWs) in non-ideal dusty plasmas comprising of electrons, ions and dust grains has been studied by self-consistently including the grain charge variations. The non-ideal effects are incorporated through the van der Waals equation of state for the dust fluid, while the charge fluctuation effects come in through the current balance equation. The real frequency and the damping rate for the linear DAWs, DCDWs and DCWs are investigated over a range of dust fugacity, defined through f = 4πndoλ2DR, where ndo is the dust number density, R is the grain size (radius) and λD is the effective plasma (electron and ion) Debye length. The reductive perturbation approach has been used to derive the governing equation for the nonlinear evolution of the various modes. The combined effects of the non-ideal contributions and the grain charge fluctuation in the linear as well as the nonlinear regimes of wave propagation have been analyzed.