| Popis: |
A discharge cell configuration combining three high-end diagnostic techniques (cross-correlation spectroscopy, electro-optic Pockels effect and laser induced fluorescence spectroscopy) has been developed. The joint application of these diagnostics enables the investigation of surface and bulk processes in barrier discharges in different arrangements. Surface charge density, N2(A) metastable state density, and optical radiation of plasma as three key parameters can be measured and correlated under identical and well-defined experimental conditions. Systematic measurements of absolute surface charge densities and nitrogen metastable concentrations are presented for different operation modes. The operation mode is mainly controlled by the gas composition, the discharge cell geometry, and the properties of the applied voltage. In particular, in pure helium the unusual Townsend-like discharge was investigated in detail. The described arrangements and the knowledge about reproducible control of discharge modes are an excellent base for the systematic investigation of the interaction between plasma and dielectric surface and its role on the formation, development, and structure of barrier discharges (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) |
Plný text