Diffraction methods and electron microscopy

Diffraction methods provide quantitative structural information of periodic structures and are therefore complementary to scanning probe microscopies. We employ both electron and x-ray diffraction to study molecular and quantum materials. A special role is played by our aberration-corrected electron spectromicroscope which combines nanometer-resolved microscopy with micro-diffraction and spectroscopic capabilities.

Group leader: Prof. Dr. Christian Kumpf

Members:
Mark Hutter, M. Sc.
You-Ron Lin, M. Sc.
Miriam Raths, M. Sc.
Hao Yin, B. Sc.

Prof. Dr. Christian Kumpf

Aberration-corrected spectro-microscopy

Aberration-corrected spectromicroscopy

We are running an aberration-corrected spectroscopic low energy electron microscope (Elmitec AC-SPE-LEEM) for real- and k-space imaging of surfaces and thin films. The microscope is one of the best of its kind in terms of spatial resolution and transmission. We use it for the observation of kinetic processes at surfaces in real time.

Chemically-resolved vertical structures with sub-Angstrom resolution

Chemically-resolved vertical structures with sub-Angstrom resolution

We employ and develop the normal incidence x-ray standing wave technique (NIXSW) to study interfaces between molecular layers and their substrates, and also (internal) interfaces of two-dimensional materials.

Heteromolecular mono- and bilayer structures

Interfaces between molecules and crystalline phases

We investigate the structural and electronic properties of interfaces between molecules and crystalline phases, because these interfaces form an integral part of almost any molecular nanostructure in which quantum functionalities may be exploited—after all, the substrate on which the nanostructure is fabricated is usually a single-crystalline material.

Epitaxial 2D Materials

Epitaxial 2D Materials

We investigate the epitaxial growth of two-dimensional materials, with the aim to optimize their quality, such that emergent properties of van der Waals heterostructures can be examined.