Numerical and Experimental Diagnostics of Dusty Plasma in a Coaxial Gridded Hollow Cathode Discharge

This paper presents the results of experimental and numerical investigation of the influence of dust nanoparticles on glow discharge plasma properties. A special apparatus was developed to provide a steady input of dust nanoparticles into ac glow discharge plasma. The plasma was created in a large-volume coaxial gridded hollow cathode. A novel simulation approach of dusty plasma was developed specifically for the experimental conditions. An extended fluid approach with drift-diffusion approximation for the electron and ion fluxes was modified to account for charged dust nanoparticles' contribution to net charge and for ion and electron loss on the surface of particles. Uniform distribution of dust particles in plasma and instantaneous charging process were assumed during simulations. Experimental measurements were carried out using Langmuir probe. Simulations and probe measurements were carried out before and after input of dust particles into plasma. Under the conditions studied both methods showed a decrease by a factor of 5 in electron density caused by input of dust nanoparticles.