|Beschreibung:||In this work the influence of external wave-like potential structures on the dynamics of drift waves in plasmas is investigated. In the center of interest is, besides a detailed, experimental investigation of the dynamics of the driven drift waves, the question, whether the anomalous fluctuation-induced transport related to drift waves can be influenced by a proper choice of the driver signal. A detailed analysis of the plasma equilibrium and a classification of the observed fluctuations as drift waves form the basis for investigations of the externally driven system. The main results of this work are: the characterization of the mode-selective interaction of drift wave and driver, the observation of temporal and spatial signatures of complete and incomplete synchronization and the identification of the influence of the azimuthal electric field of the exciter on the drift wave dynamics. These results permit an identification of the mechanism behind the observed transport enhancements and reductions. It turns out, that the radial mode structure of the driven drift modes determines the observed change of transport.
|Schlagworte:||drift wave, van der Pol, transport, probe array, synchronization, control, turbulence, open loop, periodic pulling , spatio-temporal
Driftwelle ; Periodisches Potenzial ; Transportprozess