On these pages you can find information on my scientific activities. You may also find several Matlab software for download.

I am active in the field of electron microscopy since my diploma thesis and performed various methodological studies but also applied microscopy for material science. The following list gives a brief overview of the main activities:

• Electron microscopy and related techniques for (nano)materials research
  

High resolutsion (scanning) transmission electron microsopy (HR(S)TEM),  Electron diffraction,  Electron energy-loss spectroscopy (EELS), Focused Ion Beam (FIB), Scanning electron microscopy (SEM), X-Ray Photoelectron spectroscopy (XPS),  Energie-dispersive X-Ray spectroscopy (EDX), Raman spectroscopy

Using the aforementioned techniques, I studied a big range of different (nano)materials, especially focusing on metal (Fe,Co,...) oxide nanoparticles, nanotubes made of misfit-layered compounds, TMDs, graphene and graphene oxide.

• In-situ electron microscopy

Using special sample holders, materials can be studied under external stimuli (temperature, electrical current, ...) inside a transmission electron microscope. In my studies I focused on preparation and execution of electrical in-situ experiments.

• Phase plates (PP) for transmission electron microscopy

Phase plates are a method to enhance phase contrast in TEM images. I focused on Zach-PPs, which generate the required phase shift via a micro-structured device and worked on the optimization of fabrication, the detailed analysis of image formation in experiment and simulation, the application on different samples and on the influence of inelastic scattering on phase contrast.

The hole-free PP uses a continuous thin film to induce the phase shift and I have worked on analysis of working principles of hole-free PP: Contamination and charging of thin films and analysis of phase contrast profile and image formation.

A third focus was the application of PPs in combination with aberration correction in the field of materials sciences.

• Electron-beam shaping
  

The implementation of phase masks in the condenser lens system of an electron microscope allows to shape the beam and create non-spherical beams. I focused on diffraction-free electron beams: Fabrication of phase masks made of Si3N4 and carbon and analysis of phase masks and resulting electron beams.

• Micro- and Nanostructuring

Basis for many of the methodological research was the application of micro- and nanostructuring techniques to, for example the fabrication of PPs, phase masks and in-situ chips: Optical and electron-beam lithography, thin-film evaporation, reactive ion etching, focused ion beam, thermal scanning probe lithography