Electric fields in a sheath near a metal–dielectric interface

Abstract

Spatially resolved electric fields in the sheath region near a metal–dielectric junction were measured in a radio-frequency-driven argon plasma. The fields were determined by observing the Stark shifted transitions to the 13d[3∕2]1 Rydberg state by laser-induced fluorescence-dip spectroscopy. Calibration of the Stark shifts for the 13d[3∕2]1 Rydberg state were experimentally obtained in a separate apparatus. Maps of the electric fields illustrate that the structure of the sheath formed around the junction depended on both the surface material and on the configuration of the surface.