@article{63827, abstract = {{Light-emitting diodes (LEDs) are becoming increasingly important across various sectors of the lighting industry and are being used more frequently. In the field of symbolic projection, research is increasingly focusing on implementing light modulation using energy-efficient, incoherent LEDs rather than lasers. Since light modulation in micro- and nano-optics is typically achieved through phase modulation, Finite-Difference Time-Domain (FDTD) simulations are employed for analysis. The objective of this article is to investigate different approaches for approximating incoherent monochromatic light sources within FDTD simulations. To this end, two approaches based on dipole sources are considered, as well as a method involving plane waves with modulated wavefronts based on Cosine–Fourier functions and a method based on the superposition of Gaussian beams. These methods are evaluated in terms of their accuracy using a two-dimensional double-slit configuration and are compared against a fully incoherent analytical reference.}}, author = {{Metzner, Dominik and Potthoff, Jens and Zentgraf, Thomas and Förstner, Jens}}, issn = {{2304-6732}}, journal = {{Photonics}}, keywords = {{tet_topic_opticalantenna, tet_topic_numerics, tet_topic_meta}}, number = {{2}}, publisher = {{MDPI AG}}, title = {{{Approximating Incoherent Monochromatic Light Sources in FDTD Simulations}}}, doi = {{10.3390/photonics13020128}}, volume = {{13}}, year = {{2026}}, } @article{64864, abstract = {{Probing novel properties, arising from twisted interfaces, has traditionally relied on the stacking of exfoliated two-dimensional materials and the spontaneous formation of van der Waals bonds. So far, investigations involving intimate covalent or ionic bonds have not been a focus. Yet, we show here that an established technique, involving thermocompressional wafer bonding, works well for creating twisted non-van der Waals interfaces. We have successfully bonded z-cut lithium niobate single crystals to create ferroelectric oxide interfaces with strong polar discontinuities and have mapped the associated emergent interfacial conductivity. In some instances, a dramatic change in microstructure occurs, involving local dipolar switching. A twist-induced collapse in the capability of the system to effec8tively screen interfacial bound charge is implied. Importantly, this only occurs around specific moiré twist angles with sparse coincident lattices and associated short-range aperiodicity. In quasicrystals, aperiodicity is known to induce pseudo-bandgaps and we suspect a similar phenomenon here.}}, author = {{Rogers, Andrew and Holsgrove, Kristina and Schäfer, Nils A. and Koppitz, Boris and McCluskey, Conor J. and Yedama, Shivani and Lynch, Ronan and Sloan, Keelan and Porter, Barry and Sykes, Adam and Catalan Daniels, Alex and Silva, Romualdo S. and Bruno, Flavio Y. and Seddon, Sam D. and Lu, Haidong and Rüsing, Michael and Fink, Christa and Fahler-Muenzer, Philipp and Fearn, Sarah and Heutz, Sandrine E. M. and Hadjimichael, Marios and Ramasse, Quentin M. and Alexe, Marin and Kumar, Amit and McQuaid, Raymond G. P. and Gruverman, Alexei and Sanna, Simone and Eng, Lukas M. and Gregg, J. Marty}}, issn = {{2041-1723}}, journal = {{Nature Communications}}, number = {{1}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Polar discontinuities, emergent conductivity, and critical twist-angle-dependent behaviour at wafer-bonded ferroelectric interfaces}}}, doi = {{10.1038/s41467-026-68553-7}}, volume = {{17}}, year = {{2026}}, } @article{64873, abstract = {{Continuous flow catalysis utilizing gel-bound organocatalysts within a microfluidic reactor represents a compelling strategy in the realm of organic synthesis. In this study, a quinuclidine-based catalytic monomer (QMA) was synthesized to create polymer gel dots through the process of photopolymerization that serve as a support for the catalyst. The resulting gel-bound organocatalysts were assembled within a continuous microfluidic reactor to facilitate the Baylis–Hillman reaction between various aldehydes and acrylonitrile at a temperature of 50 °C. The conversion of the product was assessed using 1H NMR spectroscopy as an offline analytical method over a duration of 8 h. The findings indicated that highly reactive aldehydes achieved conversion rates exceeding 90%, in contrast to their less reactive counterparts. Furthermore, these results were juxtaposed with previously published data derived from alternative synthetic methodologies, revealing that the continuous microfluidic reactions employing integrated organocatalysts within polymer networks exhibited significantly higher conversions with reduced reaction times (8 h) at the same temperature (50 °C). Additionally, the influence of different geometries (round, triangular, and square) of the gel dots on catalytic activity was investigated, with round and square gel dots demonstrating slightly superior performance compared with triangular gel dots, attributed to their increased surface area. Moreover, an extended reaction period of 6 days was conducted using 4-bromobenzaldehyde and acrylonitrile, resulting in a conversion rate exceeding 70%, which remained stable for 5 days before experiencing a slight decline due to product accumulation on the gel dots.}}, author = {{Killi, Naresh and Kumar, Amit and Nebhani, Leena and Obst, Franziska and Richter, Andreas and Reineke Matsudo, Bernhard and Zentgraf, Thomas and Kuckling, Dirk}}, issn = {{2470-1343}}, journal = {{ACS Omega}}, number = {{9}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Integrating an Organocatalyst into a Polymeric Gel Framework for the Continuous Microflow Baylis–Hillman Reaction}}}, doi = {{10.1021/acsomega.5c09476}}, volume = {{11}}, year = {{2026}}, } @article{61523, abstract = {{AbstractMetasurface holography offers a powerful approach for manipulating wavefronts at the nano and micro scale. Extensive research has been conducted to enhance the multiplexing capacity for diverse wavefronts. However, the independence of multiplexed channels is fundamentally restricted in techniques using single‐layer metasurfaces, resulting in unavoidable crosstalk and the need for post‐filtering of the output wavefronts. Here, a universal wavefront multiplexing concept is presented based on non‐injective transformation. By employing joint optimization on two metasurfaces, different channels can be independently designed without any constraints on the output wavefronts. To validate this approach, ultra‐compact orbital angular momentum (OAM) sorters are designed. In these experiments, the output beams from different channels can be independently mapped to 2D positions with high fineness. In another application of wavefront‐multiplexed holography, 10‐channel multiplexing is experimentally achieved with minimal crosstalk and without the need for post‐processing. These results demonstrate the independence between channels enabled by the non‐injective transformation in the method. The precise wavefront control and high multiplexing capacity underscore its potential for scalable wavefront manipulation devices.}}, author = {{Jin, Xiao and Zentgraf, Thomas}}, issn = {{0935-9648}}, journal = {{Advanced Materials}}, publisher = {{Wiley}}, title = {{{Independent Wavefront Multiplexing with Metasurfaces via Non‐Injective Transformation}}}, doi = {{10.1002/adma.202511823}}, volume = {{38}}, year = {{2026}}, } @inbook{36895, author = {{Webersen, Yvonne and Riese, Josef}}, booktitle = {{Demokratiebildung in der Lehrkräftebildung (Arbeitstitel). Paderborner Beiträge zur Bildungsforschung und Lehrkräftebildung.}}, editor = {{Becher, Andrea and Bloh, Bea and Herzig, Bardo and Pollmeier, Pascal}}, publisher = {{Waxmann}}, title = {{{Wie funktionieren (Pseudo)wissenschaften? Ein Seminarkonzept für angehende Lehrkräfte naturwissenschaftlicher Fächer}}}, volume = {{3}}, year = {{2026}}, } @article{35700, author = {{Webersen, Yvonne and Delle, Anna Luisa}}, journal = {{Plus Lucis}}, pages = {{20--23}}, title = {{{Physikalische Pseudowissenschaften entlarven am Beispiel von „WaveGuard – der Handyhülle für den gesunden Schlaf“}}}, volume = {{01/2026}}, year = {{2026}}, } @inproceedings{62885, author = {{Osnabrügge, Malin and Tenberge, Claudia and Fechner, Sabine}}, keywords = {{Artificial intelligence, primary education, science and technology education}}, location = {{Norrköping, Sweden}}, title = {{{Artificial Intelligence in primary science and technology education with a focus on implementation of AI in learning context – Results of a Scoping Review}}}, year = {{2026}}, } @article{63531, author = {{Doshi, Siddharth and Güsken, Nicholas Alexander and Dijk, Gerwin and Carlström, Johan and Ortiz-Cárdenas, Jennifer E. and Suzuki, Peter and Li, Bohan and Fordyce, Polly M. and Salleo, Alberto and Melosh, Nicholas A. and Brongersma, Mark L.}}, issn = {{0028-0836}}, journal = {{Nature}}, number = {{8096}}, pages = {{345--352}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Soft photonic skins with dynamic texture and colour control}}}, doi = {{10.1038/s41586-025-09948-2}}, volume = {{649}}, year = {{2026}}, } @article{64877, author = {{Taheri, Behnood and Kopylov, Denis and Hammer, Manfred and Meier, Torsten and Förstner, Jens and Sharapova, Polina R.}}, journal = {{arXiv}}, title = {{{Gain-induced spectral non-degeneracy in type-II parametric down-conversion}}}, doi = {{10.48550/ARXIV.2603.01656}}, year = {{2026}}, } @article{64978, abstract = {{The degrees of freedom (DoFs) of light determine the maximum number of independent signal channels an optical system can support. However, the polarization DoF is intrinsically limited to two by orthogonality, which causes unavoidable crosstalk and often forces position multiplexing, where different channels are assigned to distinct spatial locations to suppress crosstalk. This research introduces a multilayer synchronous polarization projection method that fundamentally increases the DoF for polarization multiplexing. The DoF equals twice the number of projection layers. We experimentally demonstrate six- channel polarization multiplexing holography without position multiplexing. The six-channel multiplexing results indicate that our approach exceeds the conventional polarization multiplexing method, yielding an average 3.79 dB improvement in extinction ratio across the six channels. Compared with the theoretical limit of traditional polarization multiplexing, our method reduces crosstalk by an average of 6.52 dB across all channels in a seven-channel design. The polarization projection method breaks the DoF limitation of polarization multiplexing, opening a path toward high-dimensional photonic information encoding for communication, encryption, and imaging.}}, author = {{Jin, Xiao and Zentgraf, Thomas}}, issn = {{2577-5421}}, journal = {{Advanced Photonics}}, number = {{02}}, publisher = {{SPIE-Intl Soc Optical Eng}}, title = {{{Increasing the design degree of freedom for polarization through multilayer synchronous polarization projection}}}, doi = {{10.1117/1.ap.8.2.026010}}, volume = {{8}}, year = {{2026}}, } @article{65094, abstract = {{ The development of practical sensors for optical coherence tomography (OCT) with undetected photons requires miniaturization via integration. To be practical, these sensors must exhibit a large spectral bandwidth and a high brightness, which are linked to a high axial resolution and a sufficient signal-to-noise ratio, respectively. Here, we combine these requirements in a scheme for OCT measurements with undetected photons based on nonlinear Ti : Li Nb O 3 waveguides. We investigate the performance benchmarks of the commonly used SU(1,1) scheme in comparison to an induced-coherence scheme and find that the latter is actually better suited when implementing measurements with undetected photons in integrated systems. In both schemes, we perform pump-gain optimization and OCT measurements with undetected photons with an axial resolution as low as 28 μ m . }}, author = {{Roeder, Franz and Pollmann, René and Quiring, Viktor and Eigner, Christof and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{2331-7019}}, journal = {{Physical Review Applied}}, number = {{3}}, publisher = {{American Physical Society (APS)}}, title = {{{Toward integrated sensors for optimized optical coherence tomography with undetected photons}}}, doi = {{10.1103/cwsx-42c4}}, volume = {{25}}, year = {{2026}}, } @article{65096, abstract = {{ Precise measurements of both the arrival time and carrier frequency of light pulses are essential for time–frequency-encoded quantum technologies. Quantum mechanics, however, imposes fundamental limits on the simultaneous determination of these quantities. In this work, we derive and experimentally verify the quantum uncertainty bounds governing joint time–frequency measurements. We show that when detection is restricted to finite time windows, the problem is naturally described by a quantum rotor, rendering the commonly used Heisenberg uncertainty relation inapplicable. We further propose an optimal detection scheme that saturates these fundamental limits. By sampling the Q -function, we demonstrate the reconstruction of the Wigner function beyond the harmonic oscillator. Using an experimental implementation based on a quantum pulse gate, we confirm that the proposed scheme approaches the ultimate quantum limit for simultaneous time–frequency measurements. These results provide a framework for joint time–frequency detection with direct implications for precision measurements and quantum information processing. }}, author = {{Folge, Patrick Fabian and Serino, Laura Maria and Mišta, Ladislav and Brecht, Benjamin and Silberhorn, Christine and Řeháček, Jaroslav and Hradil, Zdeněk}}, issn = {{2334-2536}}, journal = {{Optica}}, number = {{3}}, publisher = {{Optica Publishing Group}}, title = {{{Quantum-limited detection of the arrival time and the carrier frequency of time-dependent signals}}}, doi = {{10.1364/optica.579459}}, volume = {{13}}, year = {{2026}}, } @article{63451, abstract = {{Superconducting nanowire single-photon detectors (SNSPDs) can enable photon-number resolution (PNR) based on accurate measurements of the detector’s response time to few-photon optical pulses. In this work, we investigate the impact of the optical pulse shape and duration on the accuracy of this method. We find that Gaussian temporal pulse shapes yield cleaner arrival-time histograms and, thus, more accurate PNR, compared to bandpass-filtered pulses of equal bandwidth. For low system jitter and an optical pulse duration comparable to the other jitter contributions, photon numbers can be discriminated in our system with a commercial SNSPD. At 60 ps optical pulse duration, photon-number discrimination is significantly reduced. Furthermore, we highlight the importance of using the correct arrival-time histogram model when analyzing photon-number assignment. Using exponentially modified Gaussian distributions, instead of the commonly used Gaussian distributions, we can more accurately determine photon-number misidentification probabilities. Finally, we reconstruct the positive operator-valued measures of the detector, revealing sharp features that indicate the intrinsic PNR capabilities.}}, author = {{Schapeler, Timon and Mischke, Isabell and Schlue, Fabian and Stefszky, Michael and Brecht, Benjamin and Silberhorn, Christine and Bartley, Tim}}, issn = {{2835-0103}}, journal = {{APL Quantum}}, number = {{1}}, publisher = {{AIP Publishing}}, title = {{{Practical considerations for assignment of photon numbers with SNSPDs}}}, doi = {{10.1063/5.0304127}}, volume = {{3}}, year = {{2026}}, } @article{65095, abstract = {{ We provide experimental validation of tight entropic uncertainty relations for the Shannon entropies of observables with mutually unbiased eigenstates in high dimensions. In particular, we address the cases of dimensions d = 3 , 4, and 5 and consider from 2 to d + 1 mutually unbiased bases. The experiment is based on pulsed frequency bins measured with a multioutput quantum pulse gate, which can perform projective measurements on a complete high-dimensional basis in the time-frequency domain. Our results fit the theoretical predictions: the bound on the sum of the entropies is never violated and is saturated by the states that minimize the uncertainty relations. }}, author = {{Serino, Laura Maria and Chesi, Giovanni and Brecht, Benjamin and Maccone, Lorenzo and Macchiavello, Chiara and Silberhorn, Christine}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, number = {{3}}, publisher = {{American Physical Society (APS)}}, title = {{{Experimental entropic uncertainty relations in dimensions three to five}}}, doi = {{10.1103/f6c4-jtlc}}, volume = {{113}}, year = {{2026}}, } @article{65316, abstract = {{Metasurfaces are powerful tools for manipulating light using small structures on the nanoscale. In most metasurfaces, near-field couplings are treated as being unfavorable perturbations. Here, we experimentally investigate a structure consisting of sinusoidally modulated silicon waveguides where near-field coupling of local resonances leads to negative coupling, i.e., a negative coupling constant. This gives rise to wave-vector-dependent eigenstates of elliptical, linear, and circular polarizations. In particular, fully circular polarization states are not only present at a single point in momentum space (k-space) but also along a line. This circular polarization line, as well as a linear polarization line, emanates from a polarization degeneracy at the Dirac point. We experimentally validate the existence of these eigenstates and demonstrate the energy-, polarization-, and wave vector dependence of this metasurface as well as its sensitivity to fabrication tolerances. By tuning the incident k-vector, certain polarization-energy eigenstates are strongly reflected, allowing for uses in angle-tunable polarization filters and light sources.}}, author = {{Wetter, Helene and Wingenbach, Jan and Rehberg, Falk and Gao, Wenlong and Schumacher, Stefan and Zentgraf, Thomas}}, issn = {{2330-4022}}, journal = {{ACS Photonics}}, publisher = {{American Chemical Society (ACS)}}, title = {{{Polarization- and Wave-Vector Selective Optical Metasurface with Near-Field Coupling}}}, doi = {{10.1021/acsphotonics.5c02865}}, year = {{2026}}, } @inproceedings{65357, author = {{Kim, Minjun and Devaraj, Vasanthan and Seo, Hyeon-Seok and Eom, Seongjae and Lee, Jeong-Su and Lee, Donghan and Zentgraf, Thomas and Lee, Jong-Min and Jeon, Min Yong}}, booktitle = {{Quantum Sensing and Nano Electronics and Photonics XXII}}, editor = {{Razeghi, Manijeh and Khodaparast, Giti A. and Vitiello, Miriam S.}}, publisher = {{SPIE}}, title = {{{Fabrication of uniform, high-field-enhanced plasmonic satellite clusters using multidewetting}}}, doi = {{10.1117/12.3095416}}, year = {{2026}}, } @article{58493, author = {{Zietlow, Christian and Lindner, Jörg K. N.}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, number = {{1}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{An applied noise model for scintillation-based CCD detectors in transmission electron microscopy}}}, doi = {{10.1038/s41598-025-85982-4}}, volume = {{15}}, year = {{2025}}, } @article{58178, author = {{Lindner, Jörg K. N. and Zietlow, Christian}}, issn = {{0304-3991}}, journal = {{Ultramicroscopy}}, publisher = {{Elsevier BV}}, title = {{{An applied noise model for low-loss EELS maps}}}, doi = {{10.1016/j.ultramic.2024.114101}}, year = {{2025}}, } @article{59416, abstract = {{Abstract The present study explored the role of first-year physics students’ sense of belonging to physics and how it relates to their learning progression in higher education-level physics. Conducted at Paderborn University, this study examined how students’ sense of belonging to physics influences their academic outcomes in an introductory experimental physics course. Additionally, we investigated how physics students’ engagement in the Physiktreff—a holistic support program for first-year physics students to help them cope with academic and social challenges during their studies—impacts the development of their sense of belonging to physics over time. Our findings indicated that students with a stronger sense of belonging to physics performed better academically. Moreover, students who actively participated in the support program experienced a positive shift in their sense of belonging to physics. However, our findings also revealed that physics students with a higher initial sense of belonging to physics tended to experience a decline in their sense of belonging to physics during their first semester. These results underscore the importance of fostering a sense of belonging to physics within higher education, particularly during the introductory phase of students’ studies.
}}, author = {{Feser, Markus Sebastian and Bauer, Anna Brigitte}}, issn = {{0143-0807}}, journal = {{European Journal of Physics}}, publisher = {{IOP Publishing}}, title = {{{From belonging to success: Evaluating the influence of sense of belonging to physics on first-year university students’ academic outcomes and the benefits of a holistic support program}}}, doi = {{10.1088/1361-6404/adca13}}, year = {{2025}}, } @phdthesis{59608, abstract = {{Das Fachdidaktische Wissen (FDW) zählt zu den zentralen Elementen des Professionswissens (angehender) Lehrkräfte und seine Relevanz ist sowohl theoretisch angenommen als auch empirisch belegt. In der fachdidaktischen Forschung liegt daher bereits seit längerem ein Fokus auf der Analyse des FDW, wobei mittlerweile vor allem Auswirkungen auf die Handlungsqualität und auf Lernergebnisse in den Blick genommen werden. Nach wie vor stellt aber auch die empirisch fundierte inhaltliche Beschreibung des FDW sowie der Transfer entwickelter FDW-Testverfahren auf Basis von Testinstrumenten mit offenem Antwortformat in die Ausbildungspraxis ein Forschungsdesiderat dar. In diesem Dissertationsprojekt werden daher auf Basis eines Datensatzes von 846 Bearbeitungen eines FDW-Testinstruments im Fach Physik (1) projektübergreifende FDW-Kompetenzniveaus auf Basis von Item-Response-Modellierungen exploriert, (2) nicht-hierarchische FDW-Kompetenzprofile auf Basis von (probabilistischen) Cluster- und Textanalysen beschrieben und (3) ein vollständig automatisiertes FDW-Assessment-System auf Basis von Machine Learning entwickelt. Dabei wurden insbesondere kognitive Anforderungskategorien als Subskalen des verwendeten Testinstruments betrachtet. Das Assessment-System wurde dabei auf Basis dieser und weiterer Subskalen sowie anhand der Zuordnung von Proband:innen zu den Kompetenzprofilen evaluiert und zeigte sowohl relativ zur Interrater-Übereinstimmung als auch absolut betrachtet hohe Performanzwerte.}}, author = {{Zeller, Jannis}}, publisher = {{Universität Paderborn}}, title = {{{Strukturanalysen des physikdidaktischen Wissens mithilfe von Machine Learning}}}, doi = {{10.17619/UNIPB/1-2238}}, year = {{2025}}, }