Advanced Methods of Electron Microscopy
Many solid state phenomena in modern materials are not understood at the microscopic scale. For example, topological effects like Skyrmions have been observed as a lattice-like assembly of structures that are predicted to be spin vortices, the inner structure of these objects is still unknown. Another example is the structural response of new electronic materials and nanostructured devices under working conditions.
To solve these questions we explore electron-matter interaction in the electron microscope and develop and apply new in-situ transmission electron microscopy and holography. The range of questions includes the solution of phase problems by means of electron holography, the investigation of relativistic scattering and decoherence processes, as well as the analysis of local electrical, magnetic and mechanical fields.
Our specialities are the high-resolution electron holography for atomic structure analysis, electron holography and tomography in the nanometer resolution range for the measurement of three-dimensional electrical, magnetic and mechanical fields, in-situ experiments in the electron microscope, as well as the theoretical modeling of the electron-object interaction.
Our tasks can be divided into two parts: the first is the methodical development of electron microscopy. These include new optical setups, holographic and tomographic procedures, construction of in-situ experiments and the accompanying theoretical modeling. The second area comprises materials science studies. Our focus is on semiconductor technology and the study of complex oxides. A great variety of other solid-state physics problems result from the cooperation with external users. Our microscopes have special equipment for high-resolution and diffraction (structure analysis), holography and tomography (3D fields), electron energy loss spectroscopy and energy-filtered imaging (chemical element analysis).
Our experiments are carried out in close collaboration with a large number of researchers from all over the world. Amongst others we are supported by the ERC Starting Grant AToM. Close collaborations exist among others with GlobalFoundries, the Max Planck Institute for Chemical Physics of Solids and the Leibniz Institute of Polymer Research.