Dust-Acoustic Nonlinear Waves in a Nanoparticle Fraction of Ultracold (2K) Multicomponent Dusty Plasma

The nonlinear dust-acoustic instability in the condensed submicron fraction of dust particles in the low-pressure glow discharge at ultra-low temperatures is experimentally and theoretically investigated. The main discharge parameters are estimated on the basisof the dust-acoustic wave analysis. In particular, the temperature and density of ions, as well as the Debye radius, are determined. It is shown that the ion temperature exceeds the temperature of the neutral gas. The drift characteristics of all plasma fractions are estimated. The reasons for the instability excitation are considered.

Volumetric measurement of the synchronization and desynchronization of the dust acoustic wave with an external modulation

A spatio-temporal measurement showing the volumetric nature of the phase synchronization of a naturally occurring dust acoustic wave to an external modulation and the relaxation from the driven wave mode back to the naturally occurring wave mode (phase desynchronization) is presented. It is shown that the phase synchronization and desynchronization occur behind a propagating synchronization/desynchronization front that travels at a slower speed than the phase velocity of the wave and that the speed of this synchronization/desynchronization front decreases with increasing neutral gas pressure. It is also observed that volume of the wave that is synchronous depends on the frequency of the external modulation and the neutral gas pressure.