@article{61338,
  abstract     = {{Conductive ferroelectric domain walls (DWs) represent a promising topical system for the development of nanoelectronic components and device sensors to be operational at elevated temperatures. DWs show very different properties as compared to their hosting bulk crystal, in particular with respect to the high local electrical conductivity. The objective of this work is to demonstrate DW conductivity up to temperatures as high as 400 °C which extends previous studies significantly. Experimental investigation of the DW conductivity of charged, inclined DWs is performed using 5 mol % MgO-doped lithium niobate single crystals. Current–voltage (  ) curves are determined by DC electrometer measurements and impedance spectroscopy and found to be identical. Moreover, impedance spectroscopy enables to recognize artifacts such as damaged electrodes. Temperature dependent measurements over repeated heating cycles reveal two distinct thermal activation energies for a given DW, with the higher of the activation energies only measured at higher temperatures. Depending on the specific sample, the higher activation energy is found above 160 °C to 230 °C. This suggests, in turn, that more than one type of defect/polaron is involved, and that the dominant transport mechanism changes with increasing temperature. First principles atomistic modeling suggests that the conductivity of inclined domain walls cannot be solely explained by the formation of a 2D carrier gas and must be supported by hopping processes. This holds true even at temperatures as high as 400 °C. Our investigations underline the potential to extend DW current based nanoelectronic and sensor applications even into the so-far unexplored temperature range up to 400 °C.}},
  author       = {{Wulfmeier, Hendrik and Yakhnevych, Uliana and Boekhoff, Cornelius and Diima, Allan and Kunzner, Marlo and Verhoff, Leonard M. and Paul, Jonas and Ratzenberger, Julius and Beyreuther, Elke and Gössel, Joshua and Kiseleva, Iuliia and Rüsing, Michael and Sanna, Simone and Eng, Lukas M. and Fritze, Holger}},
  issn         = {{0167-2738}},
  journal      = {{Solid State Ionics}},
  publisher    = {{Elsevier BV}},
  title        = {{{Demonstration of domain wall current in MgO-doped lithium niobate single crystals up to 400°C}}},
  doi          = {{10.1016/j.ssi.2025.116949}},
  volume       = {{429}},
  year         = {{2025}},
}

@article{61337,
  abstract     = {{<jats:p>Lithium niobate–tantalate mixed (LNT) crystals promise improved performance and new applications for optical, piezomechanical, or electrical devices when compared to the end composition compounds lithium niobate and lithium tantalate. The macroscopic properties of ferroelectrics highly depend on the structure of the underlying ferroelectric domains, which within mixed crystals can interact with the local changes in chemical compositions. In this work, we demonstrate how ferroelectric domain walls can unambiguously be identified and distinguished from local changes in composition by correlating piezoresponse force microscopy with second harmonic generation microscopy, using the Cherenkov contrast, reference crystal contrast, and negative phase mismatching contrast. We demonstrate how measuring the associated intensity change when approaching negative phase mismatching can be used to deduce the local tantalum concentration fast and over a large sample area. Based on these results, we study the natural domain structures that appear from Czochralski-grown, multi-domain LNT solid solution crystals. The developed results and methods serve as the central foundation to poling these mixed crystal systems and are key for their integration and applications.</jats:p>}},
  author       = {{Koppitz, Boris and Saxena, Tanya and Bernhardt, Felix and Ganschow, Steffen and Sanna, Simone and Rüsing, Michael and Eng, Lukas M.}},
  issn         = {{0021-8979}},
  journal      = {{Journal of Applied Physics}},
  number       = {{3}},
  publisher    = {{AIP Publishing}},
  title        = {{{Second harmonic generation contrasts of ferroelectric domain structures and composition in lithium niobate–tantalate mixed crystals}}},
  doi          = {{10.1063/5.0276183}},
  volume       = {{138}},
  year         = {{2025}},
}

@article{61351,
  abstract     = {{<jats:title>Abstract</jats:title><jats:p>The interaction of water molecules with semiconductor surfaces is relevant to various optoelectronic phenomena and physicochemical processes. Despite advances in fundamental understanding of water‐exposed surfaces, the detailed time‐ and energy‐resolved behavior of excited electrons remains largely unexplored. Here, the effects of water exposure on the near‐surface electron dynamics of phosphorus‐terminated p(2×2)/c(4×2)‐reconstructed indium phosphide (100) (P‐rich InP) are studied experimentally and matched to theoretical calculations. The P‐rich InP surface, consisting of H‐passivated P‐dimers, serves as a model for other P‐containing III‐V semiconductors such as gallium phosphide (GaP) or aluminum indium phosphide (AlInP). Electron dynamics near the surface are probed with femtosecond resolution using time‐resolved two‐photon photoemission (tr‐2PPE), a pump‐probe spectroscopic technique. Pulsed water exposure preserves electronic states and significantly increases lifetimes at the conduction band minimum (CBM). Density‐functional theory (DFT) calculations attribute these findings to suppression of surface vibrational modes in the top P‐layer by water exposure, reducing electronic transition probabilities of near‐band‐gap surface states. The results suggest that many near‐surface state lifetimes reported in ultra‐high vacuum may change significantly upon electrolyte exposure. These states may thus contribute more strongly to surface reactions than traditionally assumed. Demonstrating this effect for the technologically relevant P‐rich InP surface opens new opportunities in this underexplored area of surface electrochemistry.</jats:p>}},
  author       = {{Diederich, Jonathan and Paszuk, Agnieszka and Ruiz Alvarado, Isaac Azahel and Krenz, Marvin and Zare Pour, Mohammad Amin and Babu, Diwakar Suresh and Velazquez Rojas, Jennifer and Höhn, Christian and Gao, Yuying and Schwarzburg, Klaus and Ostheimer, David and Eichberger, Rainer and Schmidt, Wolf Gero and Hannappel, Thomas and de Krol, Roel van and Friedrich, Dennis}},
  issn         = {{2196-7350}},
  journal      = {{Advanced Materials Interfaces}},
  number       = {{16}},
  publisher    = {{Wiley}},
  title        = {{{Ultrafast Electron Dynamics at the Water‐Modified InP(100) Surface}}},
  doi          = {{10.1002/admi.202500463}},
  volume       = {{12}},
  year         = {{2025}},
}

@article{61356,
  abstract     = {{<jats:p>First-principles calculations reveal how topological defects in semiconducting carbon nanotubes trap triplet excitons and enable single-photon emission at telecom wavelengths, offering new insights into their potential for photonic devices.</jats:p>}},
  author       = {{Biktagirov, Timur and Gerstmann, Uwe and Schmidt, Wolf Gero}},
  issn         = {{2040-3364}},
  journal      = {{Nanoscale}},
  number       = {{11}},
  pages        = {{6884--6891}},
  publisher    = {{Royal Society of Chemistry (RSC)}},
  title        = {{{Topological defects in semiconducting carbon nanotubes as triplet exciton traps and single-photon emitters}}},
  doi          = {{10.1039/d4nr03904a}},
  volume       = {{17}},
  year         = {{2025}},
}

@article{58519,
  abstract     = {{<jats:p>A unified theoretical approach to describe the properties of multimode squeezed light generated in a lossy medium is presented. This approach is valid for Markovian environments and includes both a model of discrete losses based on the beamsplitter approach and a generalized continuous loss model based on the spatial Langevin equation. For an important class of Gaussian states, we derive master equations for the second-order correlation functions and illustrate their solution for both frequency-independent and frequency-dependent losses. Studying the mode structure, we demonstrate that in a lossy environment no broadband basis without quadrature correlations between the different broadband modes exists. Therefore, various techniques and strategies to introduce broadband modes can be considered. We show that the Mercer expansion and the Williamson-Euler decomposition do not provide modes in which the maximal squeezing contained in the system can be measured. In turn, we find a new broadband basis that maximizes squeezing in the lossy system and present an algorithm to construct it.</jats:p>}},
  author       = {{Kopylov, Denis A. and Meier, Torsten and Sharapova, Polina R.}},
  issn         = {{2521-327X}},
  journal      = {{Quantum}},
  publisher    = {{Verein zur Forderung des Open Access Publizierens in den Quantenwissenschaften}},
  title        = {{{Theory of Multimode Squeezed Light Generation in Lossy Media}}},
  doi          = {{10.22331/q-2025-02-04-1621}},
  volume       = {{9}},
  year         = {{2025}},
}

@misc{61271,
  author       = {{Tschöpe, Cedric}},
  title        = {{{Entwicklung flammgeschützter Kunststoffpulver für das Lasersintern: Einfluss von Phosphor-, Füllstoffanteilen und Belichtungsparametern}}},
  year         = {{2025}},
}

@misc{61485,
  author       = {{Frye, Thomas}},
  title        = {{{Untersuchung der Wechselwirkungen zwischen Aluminiumdiethylphosphinat und zinkbasierten Füllstoffen als synergistische Flammschutzmittel in Polyamid 12 für das selektive Lasersintern}}},
  year         = {{2025}},
}

@article{60891,
  abstract     = {{Straight dielectric waveguide channels made from slabs of thin-film lithium niobate (TFLN), or lithium niobate on insulator (LNOI), are investigated in the linear regime, for channels of rib and strip type with common trapezoidal cross sections, in Z-cut and X-cut samples at varying on-chip orientation. We clarify the theoretical basis for the waveguides with potentially non-diagonal core permittivity. Symmetry classes can be distinguished that differ in their consequences for potential modal degeneracy and polarization conversion. Our rigorous numerical analysis by means of a finite-element solver takes the anisotropy of the lithium niobate cores rigorously into account. We discuss extensive data for effective indices, polarization properties, and hybridization of guided modes, in single- and multimode channels. Scans over the waveguide width and orientation as primary parameters are complemented by a series of illustrations of vectorial mode profiles. These turn out to be essentially complex in cases of X-cut channels at non-crystal-axis-aligned orientations.}},
  author       = {{Hammer, Manfred and Khan, Shahriar and Taheri, Behnood and Farheen, Henna and Förstner, Jens}},
  issn         = {{2770-0208}},
  journal      = {{Optics Continuum}},
  keywords     = {{tet_topic_waveguide}},
  number       = {{10}},
  pages        = {{2356}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{TFLN channel waveguides of rib and strip type: Properties of guided modes}}},
  doi          = {{10.1364/optcon.569959}},
  volume       = {{4}},
  year         = {{2025}},
}

@inproceedings{61760,
  abstract     = {{We present a topology-optimized silicon nitride (Si3N4) coupler designed to enhance the coupling efficiency between integrated single-photon emitters and photonic waveguide modes. By leveraging inverse design techniques, we optimize the coupler’s geometry to maximize power transfer while maintaining fabrication feasibility by improving mode overlap and directional emission, addressing the challenge of low coupling efficiency caused by size mismatch and material incompatibility. Simulations demonstrate a substantial enhancement in photon extraction and waveguide coupling. This approach can be extended to other photonic devices, offering a versatile framework for improving quantum light-matter interactions in integrated photonics.}},
  author       = {{Farheen, Henna and Chen, Yuheng and Chen, Peigang and Kryvobok, Artem and Peana, Samuel and Senichev, Alexander and Shalaev, Vladimir M. and Boltasseva, Alexandra and Förstner, Jens and Kildishev, Alexander V.}},
  booktitle    = {{Photonic Computing: From Materials and Devices to Systems and Applications II}},
  editor       = {{Ni, Xingjie and Cai, Wenshan}},
  keywords     = {{tet_topic_waveguide}},
  publisher    = {{SPIE}},
  title        = {{{Topology-optimized silicon nitride coupler for integrated single-photon emitters}}},
  doi          = {{10.1117/12.3065734}},
  year         = {{2025}},
}

@article{61279,
  abstract     = {{Spin waves represent an important class of low-energy excitations in magnetic solids, which influence the thermodynamic properties and play a major role in technical applications, such as spintronics or magnetic data storage. Despite the enormous advances of ab initio simulations in materials science, quantitative calculations of spin-wave spectra still pose a significant challenge, because the collective nature of the spin dynamics requires an accurate treatment of the Coulomb interaction between the electrons. As a consequence, simple lattice models like the Heisenberg Hamiltonian are still widespread in practical investigations, but modern techniques like time-dependent density-functional theory or many-body perturbation theory also open a route to material-specific spin-wave calculations from first principles. Although both are in principle exact, actual implementations necessarily employ approximations for electronic exchange and correlation as well as additional numerical simplifications. In this review, we recapitulate the theoretical foundations of ab initio spin-wave calculations and analyze the common approximations that underlie present implementations. In addition, we survey the available results for spin-wave dispersions of various magnetic materials and compare the performance of different computational approaches. In this way, we provide an overview of the present state of the art and identify directions for further developments.}},
  author       = {{Neugum, Michael and Schindlmayr, Arno}},
  issn         = {{1996-1944}},
  journal      = {{Materials}},
  number       = {{18}},
  publisher    = {{MDPI}},
  title        = {{{Ab initio calculations of spin waves: A review of theoretical approaches and applications}}},
  doi          = {{10.3390/ma18184431}},
  volume       = {{18}},
  year         = {{2025}},
}

@article{60959,
  abstract     = {{Miller's rule originated as an empirical relation between the nonlinear and linear optical coefficients of materials. It is now accepted as a useful tool for guiding experiments and computational materials discovery, but its theoretical foundation had long been limited to a derivation for the classical Lorentz model with a weak anharmonic perturbation. Recently, we developed a mathematical framework which enabled us to prove that Miller's rule is equally valid for quantum anharmonic oscillators, despite different dynamics due to zero-point fluctuations and further quantum-mechanical effects. However, our previous derivation applied only to one-dimensional oscillators and to the special case of second- and third-harmonic generation in a monochromatic electric field. Here we extend the proof to three-dimensional quantum anharmonic oscillators and also treat all orders of the nonlinear response to an arbitrary multi-frequency field. This makes the results applicable to a much larger range of physical systems and nonlinear optical processes. The obtained generalized Miller formulae rigorously express all tensor elements of the frequency-dependent nonlinear susceptibilities in terms of the linear susceptibility and thus allow a computationally inexpensive quantitative prediction of arbitrary parametric frequency-mixing processes from a small initial dataset.}},
  author       = {{Meyer, Maximilian Tim and Schindlmayr, Arno}},
  issn         = {{2673-8716}},
  journal      = {{Dynamics}},
  number       = {{3}},
  publisher    = {{MDPI}},
  title        = {{{Generalized Miller formulae for quantum anharmonic oscillators}}},
  doi          = {{10.3390/dynamics5030034}},
  volume       = {{5}},
  year         = {{2025}},
}

@article{61138,
  author       = {{Zhan, Yingjie and Caylak, Ismail and Ostwald, Richard and Barth, Enrico and Uhlmann, Eckart}},
  issn         = {{2520-8160}},
  journal      = {{Multiscale and Multidisciplinary Modeling, Experiments and Design}},
  number       = {{10}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Damage-incorporated four-step mean-field method for simulating CFRP machining: a novel algorithmic approach}}},
  doi          = {{10.1007/s41939-025-01026-4}},
  volume       = {{8}},
  year         = {{2025}},
}

@article{62034,
  abstract     = {{Effective single-particle theories, such as Hartree–Fock, density functional theory, and tight-binding, are limited by the computational cost of the self-consistent field (SCF) procedure, which typically scales cubically with the system size. This makes large-scale applications impractical without specialized algorithms and hardware. Here, we present the submatrix and graphical processing unit (GPU)-accelerated software implementation of the PTB tight-binding potential, realized in the open-source ptb codebase [M. Mueller, A. Katbashev, and S. Ehlert (2025). “grimme-lab/ptb: v3.8.1,” Zenodo. https://zenodo.org/records/17015872]. We first benchmark a traditional diagonalization-based SCF solver against density-matrix-based purification approaches, systematically varying both system size and computer hardware. Our findings show that the usage of GPUs permits shifting the boundaries to much larger systems than previously thought feasible, achieving an overall 10–15-fold performance speedup. Second, we introduce the implementation of a decomposition-type submatrix method, specifically designed for efficient operation on mid- to large-sized systems, to address the computational overhead associated with full-system diagonalization. We demonstrate that, from a certain dimension (≈104 basis functions) on, our submatrix method reduces the overall computational cost while maintaining acceptable numerical accuracy. Our study demonstrates the significance of the interplay between modern hardware, algorithmic considerations, and novel tight-binding methods, paving the way for further development in this direction.}},
  author       = {{Katbashev, Abylay and Schade, Robert and Laß, Michael and Müller, Marcel and Grimme, Stefan and Hansen, Andreas and Kühne, Thomas}},
  issn         = {{0021-9606}},
  journal      = {{The Journal of Chemical Physics}},
  number       = {{13}},
  publisher    = {{AIP Publishing}},
  title        = {{{Submatrix and GPU-accelerated implementation of density matrix tight-binding}}},
  doi          = {{10.1063/5.0271379}},
  volume       = {{163}},
  year         = {{2025}},
}

@article{62064,
  abstract     = {{SYCL is an open standard for targeting heterogeneous hardware from C++. In this work, we evaluate a SYCL implementation for a discontinuous Galerkin discretization of the 2D shallow water equations targeting CPUs, GPUs, and also FPGAs. The discretization uses polynomial orders zero to two on unstructured triangular meshes. Separating memory accesses from the numerical code allow us to optimize data accesses for the target architecture. A performance analysis shows good portability across x86 and ARM CPUs, GPUs from different vendors, and even two variants of Intel Stratix 10 FPGAs. Measuring the energy to solution shows that GPUs yield an up to 10x higher energy efficiency in terms of degrees of freedom per joule compared to CPUs. With custom designed caches, FPGAs offer a meaningful complement to the other architectures with particularly good computational performance on smaller meshes. FPGAs with High Bandwidth Memory are less affected by bandwidth issues and have similar energy efficiency as latest generation CPUs.}},
  author       = {{Büttner, Markus and Alt, Christoph and Kenter, Tobias and Köstler, Harald and Plessl, Christian and Aizinger, Vadym}},
  issn         = {{1573-0484}},
  journal      = {{The Journal of Supercomputing}},
  number       = {{6}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Analyzing performance portability for a SYCL implementation of the 2D shallow water equations}}},
  doi          = {{10.1007/s11227-025-07063-7}},
  volume       = {{81}},
  year         = {{2025}},
}

@inproceedings{62066,
  abstract     = {{In the context of high-performance computing (HPC) for distributed workloads, individual field-programmable gate arrays (FPGAs) need efficient ways to exchange data, which requires network infrastructure and software abstractions. Dedicated multi-FPGA clusters provide inter-FPGA networks for direct device to device communication. The oneAPI high-level synthesis toolchain offers I/O pipes to allow user kernels to interact with the networking ports of the FPGA board. In this work, we evaluate using oneAPI I/O pipes for direct FPGA-to-FPGA communication by scaling a SYCL implementation of a Jacobi solver on up to 25 FPGAs in the Noctua 2 cluster. We see good results in weak and strong scaling experiments.}},
  author       = {{Alt, Christoph and Plessl, Christian and Kenter, Tobias}},
  booktitle    = {{Proceedings of the 13th International Workshop on OpenCL and SYCL}},
  isbn         = {{9798400713606}},
  keywords     = {{Multi-FPGA, High-level Synthesis, oneAPI, FPGA}},
  publisher    = {{Association for Computing Machinery}},
  title        = {{{Evaluating oneAPI I/O Pipes in a Case Study of Scaling a SYCL Jacobi Solver to multiple FPGAs}}},
  doi          = {{10.1145/3731125.3731131}},
  year         = {{2025}},
}

@inproceedings{62065,
  author       = {{Sundriyal, Shivam and Büttner, Markus and Alt, Christoph and Kenter, Tobias and Aizinger, Vadym}},
  booktitle    = {{2025 IEEE High Performance Extreme Computing Conference (HPEC)}},
  publisher    = {{IEEE}},
  title        = {{{Adaptive Spectral Block Floating Point for Discontinuous Galerkin Methods}}},
  doi          = {{10.1109/hpec67600.2025.11196195}},
  year         = {{2025}},
}

@article{62166,
  author       = {{Prüßner, Tim and Hoyer, Kay-Peter and Buitkamp, Nadine and Vieth, Pascal and Grundmeier, Guido}},
  issn         = {{0254-0584}},
  journal      = {{Materials Chemistry and Physics}},
  publisher    = {{Elsevier BV}},
  title        = {{{Surface functionalisation of additively manufactured AlSi10Mg by organophosphonic acid and PDMS grafting}}},
  doi          = {{10.1016/j.matchemphys.2025.131758}},
  volume       = {{349}},
  year         = {{2025}},
}

@inproceedings{62181,
  abstract     = {{<jats:p>This research investigates how Artificial Intelligence (AI) can be systematically integrated into existing business processes by combining suitable competencies with graphical AI workflow modelling. While AI offers a high potential for automation and increased efficiency, its implementation often fails due to a lack of interdisciplinary competencies that bridge the gap between domain expertise and IT know-how. Low-code platforms and visual modelling tools are increasingly recognised as enablers, empowering non-programmers to intuitively create graphical AI- based workflows. Nevertheless, specific competencies are required to realise the full potential of AI, the domain specific knowledge and align technical understanding with AI capabilities. The paper reviews the state of the art in AI-driven business process automation and competencies for visual low-code approaches. It then presents a practical solution to identify and systematise essential competence areas. Based on this, a practical competence model is developed to support the design of user-friendly, AI-enabled workflows. This is tested in a practical application context — emergency management — where it supports critical decision-making processes and is validated through expert feedback. The study concludes by offering actionable recommendations to help organisations foster the necessary competencies and methods for competently integrating AI into their digital processes.</jats:p>}},
  author       = {{Gräßler, Iris and Özcan, Deniz}},
  booktitle    = {{AHFE International}},
  issn         = {{2771-0718}},
  location     = {{Split}},
  publisher    = {{AHFE International}},
  title        = {{{Graphical AI workflow modelling: Identifying relevant competencies in AI-based automation of business processes}}},
  doi          = {{10.54941/ahfe1006785}},
  volume       = {{198}},
  year         = {{2025}},
}

@book{62182,
  abstract     = {{<p> Executive summary Die vorliegende Zukunftsstudie „Automation 2035“ gibt einen Ausblick auf die Entwicklung der Automatisierungstechnik in den nächsten 10 Jahren. Neben der Beschreibung von Trends wie Kreislaufwirtschaft, Automatisierung der Märkte, Biologisierung, autonome Systeme und Robotik sowie IT-Sicherheit wird die zu erwartende Veränderung in der Bildung beschrieben. Dazu verwenden wir Methoden der Zukunftsforschung und arbeiten mit der Szenarientechnik, um Zukunftsperspektiven der Automation aufzuzeigen. Personas werden eingesetzt, um die zukünftigen Entwicklungen plastisch aus den Augen der Personen im Jahr 2025 und in der Zukunft im Jahr 2035 zu beschreiben. Schlüsselthemen und Trends: ... ... Inhalt Executive summary 1 1 Einführung 3 2 Zukunftsfelder für die Automatisierungstechnik 2035 4 2.1 Kreislaufwirtschaft 4 2.2 Automatisierung der Märkte 7 2.3 Biologisierung 8 2.4 Autonome Systeme und Robotik 10 2.5 Security 12 2.6 Veränderung der Ausbildung 13 3 Szenario der Automation 2035 16 4 Personas 18 4.1 Unternehmer 18 4.2 Ingenieurin 19 4.3 Schüler 20 5 Thesen und Ausblick 22 Methodik 24 Autorenteam 25 Schrifttum 26... </p>}},
  author       = {{Gräßler, Iris and Özcan, Deniz and Tusek, Alena Marie and Bilgic, Attila and Lange, Christian and Stich, Christian and Maul, Christine and Heizmann, Michael and Weyrich, Michael and Dessel,, Sascha and Miny, Torben and Jumar, Ulrich}},
  isbn         = {{9783911670180}},
  publisher    = {{VDI Verlag}},
  title        = {{{Automation 2035}}},
  doi          = {{10.51202/9783911670180}},
  year         = {{2025}},
}

@inbook{61517,
  author       = {{Alpsancar, Suzana}},
  booktitle    = {{Algorithmische Wissenskulturen. Der Einfluss des Computers auf die Wissenschaftsentwicklung}},
  editor       = {{Hashagen, Ulf and Seising, Rudolf}},
  isbn         = {{9783658355593}},
  issn         = {{2730-7425}},
  pages        = {{327–365}},
  publisher    = {{Springer}},
  title        = {{{Algorithmische Kulturen des Pflanzensammelns? Das Beispiel der Computerisierung des Botanischen Gartens und Botanischen Museums Berlin}}},
  doi          = {{10.1007/978-3-658-35560-9_14}},
  year         = {{2025}},
}