With pulsed laser ablation nanoparticles of different classes of materials are produced that are free of chemical traces and surface passivation. These can be used in, for example, medical applications.The production process is complex and involves the explosive ablation of the target material, the interaction of the particles with the liquid medium, and the dynamics of the medium itself. In order to achieve nanometer-scale sensitivity as well as a high temporal resolution, the working group uses time-resolved X-ray diffraction. In a collaboration with the University of Essen and the Paul Scherrer Institute, we image the emission of particles using small-angle X-ray scattering, and in future also with imaging methods at the ANKA (Campus Nord). A suitable experimental setup is currently being developed.
In the course of the master thesis, the flow chamber is activated with the excitation by a nanosecond laser and measurements with small-angle scattering, or X-ray imaging, are carried out. The goal is to characterize the spatial and temporal distribution of the nanoparticles in the region of the ablation-"plume". Previous experience is available from a successful experiment at the Swiss Light Source.
In the course of the bachelor thesis, the dynamics of the medium's cavity bubble is to be measured using visible range imaging methods with higher temporal resolution and compared with model calculations for the bubble dynamics.
The thesis is suitable for students with an interest in nanoscience/solid-state physics/optics who enjoy experimental work.