Multilayer X-ray mirrors using Bragg reflection are essential for applications requiring enhanced reflectivity at higher grazing incidence angles, such as hard X-ray telescopes, synchrotron beamlines, and free-electron laser optics. These mirrors are constructed from periodic bilayers of high and low refractive index materials, enabling constructive interference of reflected X-rays at...
To investigate intracellular activity and the associated deviations from thermodynamic equilibrium, we study the fluctuations of endogenous vesicles and phagocytosed beads in various cell types. Experimentally, we combine darkfield microscopy with high-speed imaging and advanced image post-processing techniques, enabling the acquisition of trajectories with spatial and temporal resolution in...
The novel perturbed tokamak concept seeks to leverage the strengths of both tokamaks and stellarators in a hybrid machine for magnetic confinement fusion. In recent work, S. Henneberg and G. Plunk (2024), as well as T. Schuett and S. Henneberg (2024) introduced a quasi-axisymmetric (QA) design that offers several advantages, including a low aspect ratio for a large plasma volume, fast particle...
Laser induced damage in dielectrics due to short pulse excitation plays a major role in a variety of scientific and industrial applications, such as the preparation of 3D structured evanescently coupled wave-guides [1] or nano-gratings [2]. The corresponding irreversible material modifications predominantly originate from higher order nonlinearities like strong field ionization and plasma...
The German Research Foundation (DFG) is the central self-governing research funding organisation in Germany and the largest of its kind. Governed by the scientific community, the DFG supports outstanding research projects and promotes collaboration among researchers. It offers a wide array of funding opportunities — ranging from individual grants to large coordinated programmes. This poster...
Aktuelle Daten zur Situation von Physikerinnen in Deutschland sowie deren Entwicklung in den letzten Jahren werden präsentiert. Während des Studiums und im Berufsleben treten immer wieder Fragen auf wie: „Werden Frauen immer noch benachteiligt?“ oder „Gibt es mittlerweile genügend weibliche Vorbilder in der Physik – gerade auch in Bezug auf die Vereinbarkeit von Familie und Beruf?“ und „Wie...
The Energetic Particle Detector (EPD) onboard ESA’s Solar Orbiter spacecraft was developed and built by the Institute for Experimental and Applied Physics at the CAU Kiel. It includes several sensors designed to measure energetic particles in the heliosphere. Among these, STEP (Suprathermal Electron and Proton Telescope) and EPT (Electron Proton Telescope), both based on silicon solid-state...
In 2022 over 360,000 premature deaths could be accounted to exposure to air pollutants in the EU member states according to the European Environment Agency (2024). The main pollutants are: Particulate Matter (PM), Ozone ($\text{O}_3$) and Nitrogen Oxides ($\text{NO}_\text{x}$ $\text{x} \in {1,2}$ ).
To decrease causalities, there has been a great effort to model air pollutants with high...
Earth-abundant electrocatalysts—such as transition metal oxyhydroxides and oxides—have emerged as promising and cost-effective alternatives to noble metals for water-splitting applications. To be viable, these electrocatalysts must meet several critical criteria, including long-term chemical stability, adequate electronic conductivity to support efficient charge transfer, and high intrinsic...
Recently, methyl chloride ($\mathrm{CH_3Cl}$) was detected with ALMA toward the infant star system IRAS 16293–2422 and with the Rosetta space probe in the atmosphere of the comet 67P/C–G$^1$. This gives rise to the question if vinyl chloride ($\mathrm{CH_2CHCl}$) might also be present in these or other astronomical sources. Previous laboratory millimeter and sub-millimeter ((sub-)mm) wave...
Precision in nanoscale material deposition is critical for advanced optical and semiconductor applications, where even slight thickness variations can degrade performance. Magnetron sputtering, a widely used plasma-based thin-film deposition technique, plays a central role in fabricating multilayer coatings for such applications. This work investigates position dependent thickness variations...
Opinion dynamics research investigates how individual opinions evolve through social interaction, producing collective patterns such as consensus, polarization, and dynamic disagreement. Classical models — including threshold, bounded confidence, averaging, and game-theoretic approaches — have provided foundational insights that continue to underpin the field. However, recent empirical...
This PhD work, entitled “Impact of resonant magnetic perturbations on plasma rotation in ASDEX Upgrade”, investigates the impact of resonant magnetic perturbations (RMPs) on plasma rotation in the ASDEX Upgrade (AUG) tokamak. To contextualize the study, it is helpful to briefly describe the fusion device. ASDEX Upgrade is equipped with 16 in-vessel saddle coils, known as B-coils, mounted on...
Spintronics is an energy-efficient alternative to conventional electronics, with potential applications in areas such as classical and quantum computing. Vanadium-doped 2H-WSe$_2$, a layered transition metal dichalcogenide, is a possible candidate for achieving the desired magnetic semiconducting behavior at room temperature with gating tunability. We grew the material using chemical vapor...
Spring in particular can carry impact-relevant extreme events over Europe, such as late frost or early summer heat. However, the dominating mechanisms and drivers of such temperature extremes in European springtime are still not fully understood. Across all seasons, one mechanism relevant for temperature extremes in Europe is atmospheric blocking. Unlike winter, where blocking is predominantly...
Neutrons decay into protons via the weak interaction through the conversion of a down quark into an up quark, emitting an electron and an electron anti-neutrino. Measurements of the electron spectrum from free neutron decay enable a variety of tests of the Standard Model of particle physics. Observables of neutron decay are, among others, the $\beta$-asymmetry $A$ and the Fierz interference...
A Positron Electron eXperiment (APEX) collaboration seeks to produce and study electron-
positron plasmas in toroidal traps. To understand these electron positron plasmas, a type of pair
plasma, we also seek to study the separate non-neutral plasmas (NNP) that will eventually be
combined.
Laboratory NNPs typically consist of only one species of charge. In this case, a pure electron
plasma...
In the last decade field-resolved infrared spectroscopy (FRS), a broadband, laser-based spectroscopic technique covering a vast part of the mid-infrared (mid-IR) range, has reached record detection sensitivities and dynamic range values [1]. This makes FRS suitable for the investigation of biological samples with high water content and in their natural aqueous environment, despite the strong...
Controlling charge density waves (CDWs) in quantum materials enables the tuning of their electronic properties, offering potential for future electronic and optoelectronic applications. 1T-TaS$_2$ exhibits various temperature-dependent CDW phases, which we aim to modify through doping. We introduced molybdenum as a dopant during the crystal growth via the chemical vapor transport method....
Addressing climate change requires sustainable, carbon-free energy sources.
A promising solution could be the use of fusion power, where electricity is generated from the heat released during nuclear fusion reactions.
For them to occur, the fuel, i.e. the hydrogen isotopes deuterium and tritium, must be in a state of plasma and exhibit sufficient temperature, density, and confinement time....
Image formation in high-resolution transmission electron microscopy (HRTEM) results in intensity projections of the interactions between the specimen and the electron beam. The recorded intensities are routinely used to reconstruct the exit wave function of the electrons, which can provide quantitative information that is otherwise not viably obtainable[1]. Prior to such analyses, it is often...
Quantum sensing allows for the highly sensitive detection of physical and chemically relevant quantities such as local magnetic fields or the presence of paramagnetic molecules, while also providing spatial resolution on the nanometer scale. A particularly powerful platform for such measurements is provided by nitrogen-vacancy (NV) centers in diamond. These consist of a nitrogen atom adjacent...
This study investigates the role of quasi-symmetry (QS) in plasma confinement in stellarators, focusing on its sensitivity to various design parameters. QS is crucial for confining trapped charged particles and plasma in toroidal magnetic fields, essential for stellarator operation. In a quasi-symmetric stellarator, although the magnetic field geometry may not be symmetric, the magnetic field...
High-throughput simulations and data-intensive experimental measurements are now central to many branches of physics, from predicting materials to benchmarking force-field models and training machine-learning potentials. Modern studies can generate terabytes of heterogeneous output files, yet much of this valuable information remains locked inside program‑specific log files, instrument...
One of the most pressing issues our society faces is the production and consumption of energy. The way how next generations will produce energy will significantly influence the environment and the future of our planet. In fusion research, our goal is to use the same physical process that powers the Sun, the fusion of light atomic nuclei to generate energy. For this, extremely high temperatures...
How can physics education be designed to increase the visibility of women physicists and support the development of a positive science identity among female students? In a higher education seminar for (prospective) physics teachers, theoretical foundations, teaching materials, and didactic strategies were explored and reflected upon with a focus on gender equity in physics. This poster...
This experiment is a simple and cost-effective setup designed to demonstrate the properties of nitrogen-vacancy (NV) centers in diamonds.
It allows for the detection of the fluorescence signal, the observation of fluorescence behavior under the influence of a microwave field, the investigation of how an external magnetic field affects the fluorescence, and the use of the system as a basic...
Quantum materials driven by strong laser fields can exhibit non-equilibrium electronic phases known as Floquet states, revealing a new domain of exciton light-matter interactions. By carefully designing the driver, it is possible to selectively excite or suppress Floquet modes, enabling enhanced control of the electronic dynamics. Floquet engineering has already been demonstrated in various...
To achieve a deeper understanding of biological processes, including immune defense and membrane remodeling, it is most important to study the interaction between proteins and the membrane. In our study, we deal with lysozyme (LYZ), which is a cationic antimicrobial protein. We would like to show the mechanism of interaction with a cell membrane and how it influences the physical and chemical...
This research was conducted as a Master’s thesis for University of Luxembourg at CERATIZIT Group, Luxembourg. Within the course of this research, the impact of impurities on the mechanical properties of cemented carbides together with their sintering behaviour are studied. The material studied here consists of submicron-sized grains as the hard phase with 10.3wt% of metallic binder. The...
