Journal Article

Positrons implanted into semiconductors can, after their thermalization, diffuse for several hundred nanometers and drift for up to a few micrometers. This behavior has been exploited technologically to produce sensitive probes of negatively charged defects, and is key to allow for the production of efficient (re)moderators and nanostructured positron-to-positronium converters. [...]

The whey protein beta-lactoglobulin (β-lg) is used as a biotemplate for the water-based synthesis of nanostructured and foam-like titania films based on its variation in supramolecular structure when denatured at different pH values. Acting as a matrix, β-lg is mixed with the water-soluble titania precursor Ti(IV) bis(ammonium lactate)dihydroxide (TiBALDh) to promote biotemplated titania precipitation. [...]

Infinite-layer (IL) nickelates have rapidly emerged as a new class of superconductors. However, due tothe technical challenges of their topotactic synthesis, they have so far been realized primarily as thin filmsor polycrystalline powder samples, limiting comprehensive investigations of fundamental physical propertiessuch as the lattice dynamics. [...]

Lithium (Li) plating on graphite is a significant degradation mechanism in Li-ion batteries. While numerous experimental techniques have been used to study Li plating in laboratory cells, investigations of commercial high-energy cells often rely on electrochemical methods. [...]

Coincidence Doppler Broadening Spectroscopy (CDBS) is a positron annihilation technique that allows the measurement of electron momenta within a sample. In CDBS both of the electron-positron annihilation gamma quanta are measured in coincidence. [...]

We introduce a novel isotope-based sample-source setup designed to enable bulk defect studies on single samples. By using the positron emitter 22Na (with an activity of 7 MBq), we have adapted the Coincidence Doppler Broadening Spectroscopy (CDBS) instrument at NEutron induced POsitron source MUniCh (NEPOMUC) accordingly. [...]

The Cu content in Al alloys significantly influences the solidification and precipitation microstructure, which is crucial for tailoring material properties in aerospace and automotive engineering applications. Cu additions affect mechanical strength, corrosion resistance, and thermal stability by promoting the formation of precipitates during artificial aging [1]. [...]

We present a novel technique for analyzing materials in situ during tensile tests using a scanning positron microbeam. Doppler broadening spectroscopy (DBS) of the 511 keV annihilation line is used to measure the variation of the local defect concentration with a resolution of (FWHM). [...]

The measurement of the 2D-angular correlation of electron positron annihilation radiation (ACAR) provides unique information about the bulk electronic structure of single crystals. We set up a new prototype for 2D-ACAR measurements using two (26.8 mm × 26.8 mm) pixelated lutetium-yttrium oxyorthosilicate scintillation (LYSO) crystals in combination with a glass light guide and (24 mm × 24 mm) multi pixel photon counters. [...]

The spinel Li$_{4}$Ti$_{5}$O$_{12}$ (LTO) has emerged as a promising anode material for the next generation of all-solid-state Li-ion batteries (ASSB), primarily due to its characteristic “zero strain” charge/discharge behavior and exceptional cycling stability, which significantly prolongs battery lifespan. Pristine LTO, however, is hindered by poor ionic and electronic conductivity. [...]