title: Collective dynamics of complex plasma bilayers.
abstract: A classical dusty plasma experiment was performed using two different dust grain sizes to form a strongly coupled asymmetric bilayer (two closely spaced interacting monolayers) of two species of charged dust particles. The observation and analysis of the thermally excited particle oscillations revealed the collective mode structure and dispersion (wave propagation) in this system; in particular, the existence of the theoretically predicted k=0 energy (frequency) gap was verified. Equilibrium molecular-dynamics simulations were performed to emulate the experiment, assuming Yukawa-type interparticle interaction. The simulations and analytic calculations based both on lattice summation and on the quasilocalized charge approximation approach are in good agreement with the experimental findings and help in identifying and characterizing the observed phenomena.
authors.affiliation: Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, H-1525 Budapest, P.O. Box 49, Hungary.
authors.forename: P
authors.initials: P
authors.lastname: Hartmann
authors.forename: Z
authors.initials: Z
authors.lastname: Donkó
authors.forename: G J
authors.initials: GJ
authors.lastname: Kalman
authors.forename: S
authors.initials: S
authors.lastname: Kyrkos
authors.forename: K I
authors.initials: KI
authors.lastname: Golden
authors.forename: M
authors.initials: M
authors.lastname: Rosenberg