Bachelor Theses

An important part of research and development (R&D) in the field of superconducting radiofrequency cavities is quench detection since these local breakdowns of superconductivity primarilylimit the cavity performance. Due to the detection of second sound waves propagating inliquid helium, the localization of quench spots on superconducting radio frequency cavities no longer requires the laborious attachment of many temperature sensors. [...]

In this bachelor thesis a feasibility study is carried out about assembling and programming a control unit for the 6 axis positioning robot EASy P1 series. The positioning robots will be used at DESY Research Center to adjust accelerator components. [...]

Perovskite solar cells are a promising photovoltaic technology with their low production costsand high efficiencies. The main reason the technology is not ready for the market yet is the instability of the perovskite absorber and its fast degradation. [...]

X-ray fluorescence measurements are an ideal method for measuring the elemental distributions in samples but complications like self absorption make the evaluation of these measurements non-trivial – especially when using multiple detector modules. This is further complicated when studying low concentrations of elements, where accurate background subtraction and elemental sensitivity is essential. [...]

Scanning X-ray microscopy measurements are an indespensible tool of solar cell research to-day, and the compatibility with complementary measurement modes is a particular strength. This Bachelor’s thesis investigates a series of thin-film solar cells with a Cu(In,Ga)Se2(CIGS) absorber layer that differ in their overall ratio of gallium to indium, resulting in a varyingbandgap. [...]

The LHC, along with all of its experiments, is going through an upgrade. The currentLHC, designed for an integrated luminosity of 300 fb$^{-1}$ , will be upgraded to the HighLuminosity LHC (HL-LHC), providing an increased collision rate and will deliver morethan 3000 fb$^{-1}$ luminosity [...]

A temperature-controlled sample environment was developed and verified for a Double Pulse Photon Correlation Spectroscopy (DPPCS) setup. Various polystyrene and ther-moresponsive Poly(N-Isopropyl Acrylamide) (pNipam) samples were characterized in Dy-namic Light Scattering (DLS) measurements [...]

This thesis studies the dynamics of a colloidal suspension, consisting of concentrated nan-oparticles with a silica core and a polymer shell of poly(N-isopropylacrylamide) (PNIPAm)suspended in water. The thermosresponsive polymer PNIPAm is known for its volume phasetransition at a lower critical solution temperature (LCST) of about 32−33◦C [...]