Matthias Dodenhöft

Ausgeschriebene Angebote für Abschlussarbeiten

Positron Remoderation for Total Reflection High-Energy Positron Diffraction

Total Reflection High-Energy Positron Diffraction (TRHEPD) is an ideal technique to determine the crystal structure of the topmost and the immediate subsurface atomic layers. In contrast to electrons, which are used in Reflection High-Energy Electron Diffraction (RHEED), positrons exhibit the phenomenon of total reflection when the glancing angle is smaller than the critical angle θ_c. For this reason, TRHEPD features outstanding surface sensitivity.

Currently, we develop a new setup that will be coupled to the high-intensity positron source NEPOMUC located at the experimental hall of the neutron source FRM II. Applying a so-called remoderation process the brightness of the positron beam can be enhanced considerably. Therefore, we expect a further reduction of the measurement time and improved statistics using the remoderated positron beam.

In the framework of this project, we are looking for a talented master student who will design, simulate and implement a positron remoderation stage. After commissioning of this device first TRHEPD and complementary RHEED measurements will be conducted.

geeignet als

• Masterarbeit Physik der kondensierten Materie
• Masterarbeit Kern-, Teilchen- und Astrophysik
• Masterarbeit Applied and Engineering Physics

Themensteller(in): Christoph Pascal Hugenschmidt