Externally driven, vertically polarized transverse dust-lattice waves were observed in a one-dimensional strongly coupled dust chain levitated in the plasma-sheath boundary of a dc argon plasma at low gas pressure around 5 mtorr. Real and imaginary parts of the complex wave number were measured in the experiments. The experimental result clearly shows that the observed transverse dust-lattice wave propagates as a backward wave, which is in good agreement with the theoretical prediction.

The drift velocity and the longitudinal diffusion coefficient of electrons in 0.206% and 1.98% ethane - argon mixtures and in pure ethane were measured in the E/N ranges 0.03 - 3 Td, 0.03 - 25 Td and 0.03 - 300 Td respectively. The measured swarm parameters in the mixtures were used to determine the essential vibrational excitation cross sections of the ethane molecule and those measured in pure ethane were used to derive the elastic momentum transfer cross section for the molecule in conjunction with the above derived vibrational cross sections. Consideration of realistic anisotropies of the electron scattering had little effect on electron swarm parameters.

A variety of dynamic behaviors in dusty plasmas is expected under the experimental condition of weak friction with gas molecules. The device “KAGEROU” provides such an environment for dynamic collective phenomena. Self-excited dust oscillations in Coulomb crystals have been observed at low values of plasma density and gas pressure. An instability mechanism was identified to be delayed charging in an inhomogeneous equilibrium dust charge in the sheath. The theoretical growth rate was formulated in relation to the destabilization of a transverse dust lattice wave (T-DLW), which was found to be very sensitive to the presence of a small amount of hot electrons which produces a substantial positive equilibrium charge gradient ∇Qd-eq around the equilibrium position of dust particles in the plasma–sheath boundary. The first experimental observation of a correlated self-excited vertical oscillations in a one-dimensional dust chain indicates a destabilization of T-DLW. The experimental condition is very consistent with the parameter area which predicts numerically an instability of T-DLW.

The parameters of self-consistent dusty sheaths are investigated using computer simulations of the temporal evolution of one-dimensional slab plasma with two-temperature electrons and dust particles. The evolution is caused by collection of electrons and ions by an electrode (wall) and also by dust particles, which are initially injected into the plasma around the electrode (wall). A peculiarity of the sheaths is a nonmonotonic spatial distribution of the electric potential that causes protection of the electrode (wall) from fast ions. The degree of protection depends on the temperature and density ratios of both electron components.

Thermoelectrons emission from plasma facing components has been studied using 2-D particle in cell simulation code (Berkeley code). The precise evaluation of the thermoelectrons emission current in plasmas is essential to study the plasma heat flow to the material surface, for example, the formation of the hot spot. It is found that the space-charge limited current strongly depends on whether the periphery of the hot spot is insulator or conductor which is due to the modification of potential profiles in front of the plasma-facing components.