Research interests
The focus of our group is on experimental plasma physics.
While the two-body problem can in general still be solved quite well analytically, the complexity is already increased considerably for only three bodies. In plasmas, however, particle densities on the order of 1015 to 1019 m-3 are generated, so these systems must be described using the methods of statistical physics. In addition, there are Coulomb forces acting on the charge, so plasmas exhibit collective behavior.
Plasmas play a major role in nature and technology. 99.9 % of the visible matter in the universe is in the plasma state. In contrast to astrophysical plasmas, all plasmas generated on Earth are in contact with surrounding media. The influence of such a medium fundamentally determines its properties, for example by the balance between particle generation and energy coupling in the plasma and losses at the surface. Conversely, the value of plasmas for technology even results directly from the influence of the plasma on the medium, e.g. more than 70 % of all process steps for the production of microelectronic components are based on plasma surface processes. Nevertheless, there are still major deficiencies in the description of non-equilibrium processes at this interface. Often the description is purely empirical and does not take into account the reciprocity of the processes at the corresponding interface between plasma and medium, for example when using secondary electron coefficients or sputtering rates. However, knowledge of these processes is essential for the further development of plasma technology, e.g. in the use of plasmas in catalysis for the production of CO2-neutral fuels.
In order to replace the empirical description with physical models, we design our plasma sources and our experiments specifically with this question in mind. For analysis, we use both plasma and surface diagnostics. We place great emphasis on supporting our complex experiments with simple model calculations and making the outcome of the experiments comparable to simulations.
Current research topics are charge effects of dielectrically barrier surface discharges, the interaction of plasmas and surfaces under the influence of laser radiation, and the use of plasmas in biocatalysis and medical applications.
- plasma interface
- atmospheric pressure plasma physics
- plasma chemistry in reactive plasmas
- reference sources and characterization measurements for plasma medicine
- plasma diagnostics:
- electrical power measurements
- (phase-resolved) optical emission spectroscopy
- ultraviolet spectroscopy
- laser absorption spectroscopy
