Dust-acoustic surface wave stability in dusty Lorentzian Plasmas

Abstract

The dispersion relation of dust-acoustic surface waves (DASW) propagating on the interface between a vacuum and a semi-bounded dusty Lorentzian plasma is derived using a standard kinetic approach. The real and the imaginary parts of the wave frequency w(r) + i gamma are obtained as functions of the scaled wave number root mu(kappa)k(x)lambda(D), where mu(kappa) = (2 kappa - 3)/(2 kappa - 1) with K being the spectral index of the Lorentzian distribution function and lambda(D) being the total Debye length of ions and electrons. The wave displays Landau damping for all wave numbers, but can be significantly reduced as the wave number increases. The maximum damping rates are obtained as functions of the spectral index and the ion-to-electron density ratio.