Generation of dusty plasmas in supercritical carbon dioxide using surface dielectric barrier discharges

Abstract

Dusty plasmas are a class of plasmas that not only have repercussions for many branches of plasma science and technology, but also thermodynamics and statistical mechanics. However, in ground-based experiments, gravity influences the dynamics and formation of plasma crystals, and the realization of zero-gravity dusty plasmas in space is very costly and time-consuming. To overcome some of these limitations, we propose dusty plasmas in supercritical fluids as a means for realizing ground-based experiments under pseudo-microgravity conditions, to study the formation and self-organization of plasma crystals. Dusty plasmas were realized by using surface dielectric barrier discharges (DBDs) generated in supercritical carbon dioxide (), and the motion of fine particles above the electrode surface was studied by high-speed imaging. The plasmas deposited charge on the particles, and the particles formed a self-organized structure above the surface DBD reactor. The particle charge estimated from the analysis of particle motion was on the order of −104 to −105e C, and the estimation of the Coulomb coupling parameter of the charged particles with a value of 102 to 104 confirmed the formation of strongly coupled plasmas.