Dust as probe for horizontal field distribution in low pressure gas discharges

Abstract

Using dust grains as probes in gas discharge plasma is a very promising, but at the same time very challenging method, as the individual external control of dust grains has to be solved. We propose and demonstrate the applicability of the RotoDust experiment, where the well controlled centrifugal force is balanced by the horizontal confinement field in plane electrode argon radio frequency gas discharges. We have reached a resolution of 0.1 V/cm for the electric field. This technique is used to verify numerical simulations and to map symmetry properties of the confinement in dusty plasma experiments using a glass box.