Physicists may not be exceptional – but they are the exception. Most people do not have an aca-demic background in science beyond their school years. Yet, science plays a vital role in all our lives. As scientists, we depend on public support to fund research, and as a society, we depend on scientific knowledge to address complex, so-called “wicked problems” like climate change or pandemics...
This presentation will gives an overview of ongoing research into acoustic wave behaviour in both fluids and solids applications, highlighting their generation, propagation, and mitigation. From low-order modelling of aero- and hydroacoustic instabilities in piping systems, sonic cavitation and bubble dynamics to acoustic MEMS sensors, we will address the challenges of predicting and...
In light of the current climate crisis, scientists around the world are searching for innovative solutions that could play a major role in the electrification of the industry. A new focus in this field is the combination of plasmas with catalysis as a key process to store renewable energy in chemical resources. Plasma catalysis is an emerging interdisciplinary field at the intersection of...
The Cluster of Excellence Quantum Universe at the University of Hamburg and DESY cordially invites final year Master students, doctoral researchers and postdoctoral researchers in particle physics, astroparticle physics, astrophysics and mathematical physics/mathematics to our Attract.Workshop. The Workshop gives you the chance to discover our labs. Meet our researchers. Explore your future....
The Standard Model has been proven to be valuable theory for explaining the funda-
mental principles of particle physics, however, some open questions still remain. Amongst
other things, these questions revolve around neutrinos, particularly why they are so much
lighter than other leptons. Furthermore, the Standard Model only contains left-handed
neutrinos, as right-handed ones, also known...
Understanding and controlling the properties of materials at the atomic level is the basis for modern, sustainable technologies. We therefore need methods that provide precise insights into the structure and dynamics of matter - e.g. synchrotron radiation, neutrons and ion beams, which are available in large-scale research facilities. Research highlights show the potential of these probes....
We are searching for long-lived Axion-Like Particles produced in association with a top-antiquark pair, in proton-proton collisions with the CMS detector at the LHC. Compared to inclusive searches for a displaced vertex, top quark-associated signals offer new trigger options and an extra handle to suppress background. The search strategy includes axion-like particle decays to a displaced...
The Earth is constantly hit by energetic particles originating from galactic sources. The flux of these particles is altered by the magnetized solar wind in the heliosphere. These modulation effects occur on different timescales: long-term variations are driven by the 11-year solar cycle, while short-term decreases are caused by transient structures such as Forbush decreases (FDs).
In this...
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...
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...
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...
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...
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...
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...
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...
Phosphorus is a vital nutrient for agriculture and fertiliser production. However, it is in limited supply across Europe, resulting in heavy dependence on imports. Promising substitutes for phosphorus recovery have been found to be municipal sewage sludge and wastewater [1]. But present techniques of removal mostly chemical precipitation with iron salts cause non-bioavailable iron phosphate...
Iridium complexes have highly interesting photochemical, photophysical and catalytic properties. They are used for example in organic light-emitting diodes (OLEDs), organic solar cells and automotive exhaust catalysts.[1,2,3] Iridium complexes have also been used to initiate "water oxidation reactions“.[4,5] They also hold promise as photosensitisers and photocatalysts for directed...
The structural and electronic properties of CrOx/Pt(111) films were investigated by LEED, XPS and LT-STM in combination with DFT calculations performed via a genetic algorithm [1]. Depending on the nominal Cr coverage and the oxygen-chemical potential during deposition, two unique oxide phases were identified. A (√3×√3)R30° phase emerges at sub-monolayer Cr-exposure and O-rich oxidation...
Thin films of Aluminium-Scandium Nitride (AlScN) are used as central components in magnetoelectric surface-acoustic wave sensors utilized extensively within the Collaborative Research Center 1261 "Biomagnetic Sensing".
High resolution XRD experiments were conducted at microfocus beamline P10 at PETRA III. Bragg diffraction on AlScN thin films grown on GaN was investigated at the [0 0 0 2] and...
The Novatron [1] is a novel, axisymmetric, magnetic mirror-cusp device. The magnetic field configuration produces favourable curvature at the outer plasma surface that should be inherently stable against interchange instabilities that have troubled previous magnetic mirror devices. Open field line magnetic confinement systems have faced four critical challenges: MHD interchange instabilities...
Recent years have seen a steady flow of media reports about cases of unethical behaviour in academia. Such behaviour seems to be surprisingly common, often cause great damage, and typically remain unsanctioned. In my talk, I will first introduce a number of concepts that are relevant to the discourse on this topic (e.g., power, abuse of power). Then I will discuss some key factors that may...
Geschlecht geht weit über Männer, Frauen und das sogenannte „dritte“ Geschlecht hinaus, geschlechtsspezifische Diskriminierung ebenso. Insbesondere in der höheren Bildung und klassischen „Männerberufen“ wie den Naturwissenschaften sorgt diese Ungleichheit für alltägliche Probleme und behindert Lehre, Forschung und Wissenschaft.
Der Vortrag bietet einen kurzen Überblick über die Vielfalt von...
Polaritonic quasiparticles in two-dimensional (2D) materials have emerged as a powerful platform for studying light–matter interactions and mediating novel photon- and phonon-driven correlations between electronic excitations. In this work, we employ electron beam-based techniques to probe exciton and plasmon polaritons across a diverse set of 2D materials, including transition metal...
Nuclear fusion offers the prospect of a sustainable and base load capable source of energy, produced in a high-temperature plasma of deuterium and tritium. One of the most advanced approaches to achieve reactor-relevant conditions is magnetic confinement of the plasma. In the tokamak configuration, the plasma is enclosed in an axisymmetric toroidal magnetic field, established using external...
The first four women to obtain a PhD in physics at Leiden University all graduated with Nobel laureate Hendrik Lorentz. Hendrika Johanna (Jo) van Leeuwen (1887−1974) was one of them. Her thesis elucidates that magnetism is exclusively a quantum phenomenon – a result that was independently also obtained by Niels Bohr and that is now commonly known as the Bohr–van Leeuwen theorem. From 1920...
MoS$_2$ has recently emerged as a promising material for enabling quantum devices and spintronic applications. In this context, the demonstration of resistively detected electron spin resonance (RD-ESR) and the determination and improved physical understanding of the g factor are of great importance. However, its application and RD-ESR studies have been limited so far by Schotttky or...
Junge Frauen sind in Physik ab der Sekundarstufe II nach wie vor unterrepräsentiert. Sie zeigen ein vergleichsweise geringeres Interesse an Physik und sind bei gleicher Leistung in geringerem Maße als zum Beispiel junge Männer davon überzeugt, physikalische Aufgaben mit ihren Fähigkeiten bewältigen zu können. Dies ist problematisch, da sowohl fundierte Physikkenntnisse als auch vielfältige...
Controlling light–matter interactions at the molecular level is a fundamental challenge in physics, with broad implications for chemistry and material science. Selective electronic excitation becomes particularly challenging within molecular mixtures, especially when species share nearly identical UV/VIS absorption spectra. We demonstrate how Vibrationally Promoted Electronic Resonance (VIPER)...
electronCT (eCT) is a new imaging method, which uses multiple scattering of electrons to determine the material budget of objects. This imaging method could be used in the context of FLASH radiotherapy with very high energy electrons (50-250 MeV). A pencil beam of MeV electrons is aimed at an object and the widening of the beam is measured, where the widening of the beam is dependent on the...
Large language models (LLMs) are now widely accessible, reaching learners at all educational levels. Their rapid adoption has sparked concerns that students may use them in ways that bypass essential learning processes and undermine the integrity of established assessment formats. In physics education, where problem solving is at the heart of both teaching and assessment, these concerns are...
Quantum technologies are key emerging technologies with promising potential. Quantum computers will expand and complement existing classical and powerful supercomputers and fundamentally transform industries that rely on large-scale computations. For example, quantum computing offers new possibilities for solving problems that cannot be addressed using classical methods, such as simulating...
Synopsis
We attempted to implement a whole-brain NAA (wbNAA) spectroscopy sequence in a vendor-agnostic environment. During the 16 repeated acquisitions, we observed large fluctuations of the water signal exceeding 50%. It was demonstrated that these instabilities originate from the binomial 1¯3 3¯1 excitation pulse. Ongoing work aims to identify the underlying cause of this...
Topological nanophotonic systems offer robust light propagation modes with immunity to defects, holding promise for quantum technologies and advanced optical devices.[1] However, designing such structures under nonplanar excitation remains computationally intensive due to high-dimensional design spaces and nonlinear interactions. I introduce a physics-informed deep learning framework that...
Despite the importance of Digital Data Acquisition (DDA) for research in the physical sciences and in our daily lives, physics teachers seem to shy away from utilizing these tools for their teaching on a regular basis. With the aim of supporting teachers in planning and implementing DDA in their lessons, we developed a multi-part professional development program (PD), where teachers can...
The top quark holds a unique place in nature as the heaviest known elementary particle: with a mass comparable to that of a gold atom, it is the particle with the strongest coupling to the Higgs boson, which was discovered at the Large Hadron Collider (LHC) in 2012. The top quark considered one of the most promising probes of phenomena beyond the SM, such as additional Higgs bosons or heavy...
Precision agriculture, which involves the use of sensors, information databases, and high-tech machinery, can improve agricultural productivity achieving high yields with targeted fertilization. Today, soil nutrient measurements typically require manual soil sampling. First electrochemical sensors have been deployed in the field and show promising results, while still requiring manual...
Particles beyond the standard model (SM) can generically have lifetimes that are long compared to SM particles at the weak scale. When produced at experiments such as the Large Hadron Collider (LHC) at CERN, these long-lived particles (LLPs) can decay far from the interaction vertex of the primary proton–proton collision. Such LLP signatures are distinct from those of promptly decaying...
Photoelectron spectra from strong-field ionization show features like
energy cutoffs and interference patterns, influenced by direct and
backscattered electrons [1]. The typical cut-offs at 2𝑈𝑝 and 10𝑈𝑝
can be explained within the famous three-step model, while quantum
inter- and intracycle interferences are typically associated with selfinterference
of direct or backscattered,...
Metallic microstructures have become a topic of great interest for many fields due to their conducting and magnetic properties. Conventional Direct Laser Writing (DLW) is a versatile method for additive manufacturing of microscale polymeric structures. Despite the fact that many applications would benefit from the ability to directly print metallic and especially ferromagnetic microstructures,...
At the Small Quantum Systems (SQS) scientific instrument at the European X-ray Free Electron Laser (XFEL), ultrashort, intense soft x-ray pulses are used to irradiate and often multiple-ionize samples in the gas phase, such as atoms, molecules, or nanoparticles in a vacuum environment. To investigate those samples, various spectroscopic techniques are employed. One of them is Velocity Map...
Conventional photosensitizers (PSs) for photocatalysis are typically derived from rare and valuable precious metals, prompting the search for alternatives based on first-row transition metals [1, 2, 3]. Among these, iron-based photosensitizers emerge as potential candidates but are limited by their short-lived charge transfer states. To overcome this limitation, targeted ligand design is...
Homogeneous electrocatalysis based on transition metal complexes holds great potential for carbon dioxide utilization. In order to develop an efficient catalytic system, detailed knowledge about each step of the complex reaction chain is highly desirable. Until now, only long-lived intermediates have been observed. Therefore, the identification of short-lived intermediates and the...
