@article{59056,
  author       = {{Seeger, Karl and Genovese, Matteo and Schlüter, Alexander and Kockel, Christina and Corigliano, Orlando and Díaz Canales, Edith Benjamina and Praktiknjo, Aaron and Fragiacomo, Petronilla}},
  issn         = {{0360-3199}},
  journal      = {{International Journal of Hydrogen Energy}},
  pages        = {{558--576}},
  publisher    = {{Elsevier BV}},
  title        = {{{Techno-economic analysis of hydrogen and green fuels supply scenarios assessing three import routes: Canada, Chile, and Algeria to Germany}}},
  doi          = {{10.1016/j.ijhydene.2025.02.379}},
  volume       = {{116}},
  year         = {{2025}},
}

@article{60837,
  abstract     = {{In light of growing demands for resource efficiency and sustainability in vehicle engineering, the environmentally compatible separation of structural adhesive joints is gaining increasing relevance. This study presents a comparative analysis of two physically based debonding methods: the established hot-air process and a cryogenic cold process based on liquid nitrogen (LN2). The primary objective is to assess the ecological impact and process-related sustainability of both approaches.
Experimental investigations were conducted on a component-representative triple-sheet structure that simulates common automotive flange joints. Thermal input was applied either by convective heating using a hot air gun or by direct cooling through a contact-based LN2 tool. The resulting temperature profiles were recorded using spatially distributed thermocouples. Subsequently, the outer panel was selectively debonded to replicate a repair scenario, and the mechanical integrity of the remaining adhesive joint was evaluated through Mode I testing of L-shaped specimens. Process data served as input for an Life Cycle Assessment (LCA) according to DIN EN ISO 14040.
The cryogenic method achieved a 40% reduction in carbon footprint compared to the hot-air process (0.337 kg vs. 0.559 kg CO2-equivalents), primarily due to its shorter process time and more efficient heat transfer. While the hot-air method’s impact is mainly driven by electrical energy use, that of the cold method stems from cryogenic media consumption. Notwithstanding certain disadvantages in specific impact categories, the LN2-based process exhibits a superior overall ecological performance and signifies a promising solution for repair- and recycling-oriented adhesive separation in structural vehicle applications.}},
  author       = {{Jordan, Alex and Hermelingmeier, Lucas and Gilich, Julian and Meschut, Gerson and De Santis, Marco Sebastian and Schlüter, Alexander}},
  issn         = {{2666-3309}},
  journal      = {{Journal of Advanced Joining Processes}},
  keywords     = {{Sustainable debonding, Structural adhesives, Sustainable joining technologies, Life Cycle Assessment (LCA), Automotive repair process, Economically efficient debonding}},
  publisher    = {{Elsevier}},
  title        = {{{Comparison of the economic efficiency and sustainability of two debonding processes for structurally bonded sills}}},
  doi          = {{10.1016/j.jajp.2025.100332}},
  volume       = {{12}},
  year         = {{2025}},
}

@article{60681,
  author       = {{Díaz Canales, Edith Benjamina and Avila Galarza, Alfredo and Schlüter, Sabine and Lacayo Escobar, Erick and Schlüter, Alexander}},
  issn         = {{3044-5221}},
  journal      = {{Journal of Sustainable Development Indicators}},
  number       = {{2}},
  pages        = {{1--26}},
  publisher    = {{SDEWES Centre}},
  title        = {{{Implementing Strategic Environmental Assessment in the Global South, a Challenge: Nicaragua as a Case Study}}},
  doi          = {{10.13044/j.sdi.d2.0592}},
  volume       = {{1}},
  year         = {{2025}},
}

@inbook{59841,
  author       = {{Genovese, Matteo and Piraino, Francesco and Corigliano, Orlando and Schlüter, Alexander and Scionti, Eugenio and Fragiacomo, Petronilla}},
  booktitle    = {{Accelerating the Transition to a Hydrogen Economy}},
  isbn         = {{9780443240027}},
  publisher    = {{Elsevier}},
  title        = {{{Hydrogen economy development in the European Union}}},
  doi          = {{10.1016/b978-0-443-24002-7.00005-7}},
  year         = {{2025}},
}

@article{63091,
  abstract     = {{We present the design and characterization of a guided-wave, bright, and highly frequency non-degenerate parametric down-conversion (PDC) source in thin-film lithium niobate. The source generates photon pairs with wavelengths of 815 nm and 1550 nm, linking the visible wavelength regime with telecommunication wavelengths. We confirm the high quality of the generated single photons by determining a value for the heralded second-order correlation function as low as g_h^(2)=(6.7+/-1.1)*10^8-3). Furthermore, we achieve a high spectral brightness of 0.44·10pairs/(smWGHz) which is two orders of magnitude higher than sources based on weakly guiding waveguides. The shape of the PDC spectrum and the strong agreement between the effective and nominal bandwidth highlight our high fabrication quality of periodically poled waveguides. The good agreement between the measured and simulated spectral characteristics of our source demonstrates our excellent understanding of the PDC process. Our result is a valuable step towards practical and scalable quantum communication networks as well as photonic quantum computing.}},
  author       = {{Babel, Silia and Bollmers, Laura and Roeder, Franz and Ridder, Werner and Golla, Christian and Köthemann, Ronja and Reineke, Bernhard and Herrmann, Harald and Brecht, Benjamin and Eigner, Christof and Padberg, Laura and Silberhorn, Christine}},
  issn         = {{1094-4087}},
  journal      = {{Optics Express}},
  number       = {{25}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{Ultrabright, two-color photon pair source based on thin-film lithium niobate for bridging visible and telecom wavelengths}}},
  doi          = {{10.1364/oe.571605}},
  volume       = {{33}},
  year         = {{2025}},
}

@article{62713,
  abstract     = {{Periodically poled thin-film lithium niobate (TFLN) crystals are the fundamental building block for highly-efficient quantum light sources and frequency converters. The efficiency of these devices is strongly dependent on the interaction length between the light and the nonlinear material, scaling quadratically with this parameter. Nevertheless, the fabrication of long, continuously poled areas in TFLN remains challenging, the length of continuously poled areas rarely exceeds 10 mm. In this work, we demonstrate a significant progress in this field achieving the periodic poling of continuous poled areas of 70 mm length with a 3 μm poling period and a close to 50 % duty cycle. We compare two poling electrode design approaches to fabricate long, continuous poled areas. The first approach involves the poling of a single, continuous 70 mm long electrode. The second utilize a segmented approach including the poling of more than 20 individual sections forming together a 70 mm long poling area with no stitching errors. While the continuous electrode allows for faster fabrication, the segmented approach allows to individually optimize the poling resulting in less duty cycle variation. A detailed analysis of the periodic poling results reveals that the results of both are consistent with previously reported poling outcomes for shorter devices. Thus, we demonstrate wafer-scale periodic poling exceeding chiplet-size without any loss in the periodic poling quality. Our work presents a key step towards highly-efficient, narrow-bandwidth and low-pump power nonlinear optical devices.}},
  author       = {{Bollmers, Laura and Spiegelberg, Noah and Rüsing, Michael and Eigner, Christof and Padberg, Laura and Silberhorn, Christine}},
  issn         = {{2192-8606}},
  journal      = {{Nanophotonics}},
  pages        = {{4761}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Segmented finger electrodes to optimize ultra-long continuous wafer-scale periodic poling in thin-film lithium niobate}}},
  doi          = {{10.1515/nanoph-2025-0461}},
  volume       = {{14}},
  year         = {{2025}},
}

@misc{63051,
  author       = {{Güsken, Nicholas Alexander}},
  title        = {{{Optical modulator and electronic apparatus including the same}}},
  year         = {{2025}},
}

@article{63534,
  abstract     = {{<jats:p>Boson sampling is a key candidate for demonstrating quantum advantage and has already yielded significant advances in quantum simulation, machine learning, and graph theory. In this work, a unification and extension of distinct forms of boson sampling is developed. The devised protocol merges discrete-variable scattershot boson sampling with continuous-variable Gaussian boson sampling. Therefore, it is rendered possible to harness the complexity of more interesting states, such as squeezed photons, in advanced sampling protocols. A generating function formalism is developed for the joint description of multiphoton and multimode light undergoing Gaussian transformations. The resulting analytical tools enable one to explore interfaces of different photonic quantum-information-processing platforms. A numerical simulation of unified sampling is carried out, benchmarking its performance, complexity, and scalability. Entanglement is characterized to exemplify the generation of quantum correlations from the nonlinear interactions of a unified sampler.</jats:p>}},
  author       = {{Bianchi, Luca and Marconi, Carlo and Ares, Laura and Bacco, Davide and Sperling, Jan}},
  issn         = {{2643-1564}},
  journal      = {{Physical Review Research}},
  number       = {{4}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Unified boson sampling}}},
  doi          = {{10.1103/8hy1-m5gg}},
  volume       = {{7}},
  year         = {{2025}},
}

@article{63562,
  abstract     = {{<jats:p>Entangled two-mode Gaussian states constitute an important building block for continuous variable quantum computing and communication protocols. In this work, we theoretically study two-mode bipartite states, which are extracted from multimode light generated via type-II parametric downconversion (PDC) in lossy waveguides. For these states, we demonstrate that the squeezing quantifies entanglement and we construct a measurement basis, which results in the maximal bipartite entanglement. We illustrate our findings by numerically solving the spatial master equation for PDC in a Markovian environment. The optimal measurement modes are compared with two widely used broadband bases: the Mercer–Wolf basis (the first-order coherence basis) and the Williamson–Euler basis.</jats:p>}},
  author       = {{Kopylov, Denis and Meier, Torsten and Sharapova, Polina R.}},
  issn         = {{2835-0103}},
  journal      = {{APL Quantum}},
  number       = {{4}},
  publisher    = {{AIP Publishing}},
  title        = {{{Bipartite entanglement extracted from multimode squeezed light generated in lossy waveguides}}},
  doi          = {{10.1063/5.0293116}},
  volume       = {{2}},
  year         = {{2025}},
}

@unpublished{58544,
  abstract     = {{We introduce a new classification of multimode states with a fixed number of photons. This classification is based on the factorizability of homogeneous multivariate polynomials and is invariant under unitary transformations. The classes physically correspond to field excitations in terms of single and multiple photons, each of which being in an arbitrary irreducible superposition of quantized modes. We further show how the transitions between classes are rendered possible by photon addition, photon subtraction, and photon-projection nonlinearities. We explicitly put forward a design for a multilayer interferometer in which the states for different classes can be generated with state-of-the-art experimental techniques. Limitations of the proposed designs are analyzed using the introduced classification, providing a benchmark for the robustness of certain states and classes. }},
  author       = {{Kopylov, Denis and Offen, Christian and Ares, Laura and Wembe Moafo, Boris Edgar and Ober-Blöbaum, Sina and Meier, Torsten and Sharapova, Polina and Sperling, Jan}},
  title        = {{{Multiphoton, multimode state classification for nonlinear optical circuits }}},
  year         = {{2025}},
}

@article{59069,
  abstract     = {{<jats:p>Stable and bright single photon sources are key components for future quantum applications. A simple fabrication method is an important requirement for such sources. Here, we present a single photon source based on diced ridge waveguides in titanium indiffused LiNbO<jats:sub>3</jats:sub>. These waveguides can be easily fabricated by combining planar titanium in-diffusion without lithographic patterning and easy-to-handle precision dicing. Such devices have the potential to generate high single photon rates because ridge structures are typically less prone to the photorefractive effect. We achieve waveguide propagation losses &lt;0.4dBcm and a SHG conversion efficiency of about 81%Wcm<jats:sup>2</jats:sup>. Harnessing a type-0 SPDC process to generate 1550 nm photons, we obtain a SPDC brightness of 3⋅10<jats:sup>5</jats:sup>1s⋅mW⋅nm, with a heralding efficiency of <jats:italic>η</jats:italic><jats:sub>h</jats:sub>=45% (<jats:italic>η</jats:italic><jats:sub>h,wg</jats:sub>=77.5% for the waveguide itself excluded setup losses) and a heralded second-order correlation function of <jats:italic>g</jats:italic><jats:sub>h</jats:sub><jats:sup>2</jats:sup>(0)&lt;0.003 at low pump powers.</jats:p>}},
  author       = {{Kießler, Christian and Kirsch, Michelle and Lengeling, Sebastian and Herrmann, Harald and Silberhorn, Christine}},
  issn         = {{2770-0208}},
  journal      = {{Optics Continuum}},
  number       = {{3}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{SPDC single-photon source in Ti-indiffused diced ridge LiNbO<sub>3</sub> waveguides}}},
  doi          = {{10.1364/optcon.557439}},
  volume       = {{4}},
  year         = {{2025}},
}

@article{59130,
  author       = {{Kleinschmidt, Dennis and Brüning, Florian}},
  journal      = {{KGK Kautschuk Gummi Kunststoffe}},
  keywords     = {{Rheologie, Viskosität, Wandgleiten}},
  title        = {{{Influence of pre-shearing on the rheological properties of filled rubber compounds}}},
  year         = {{2025}},
}

@article{59276,
  abstract     = {{Stress plays a crucial role in thin films and layered systems, and thus significantly influences the material's electrical, mechanical and (nonlinear) optical responses. Despite lithium niobate's wide applicability as a nonlinear optical material, the impact of mechanical stress on its nonlinear optical properties is not well characterized. In this work, we systematically study both experimentally and theoretically, the nonlinear optical responses of thin film lithium niobate (TFLN) single crystals. Compressive and tensile stress is applied in our experiment using a piezodriven strain cell. We then record the second-harmonic-generated (SHG) response in back-reflection geometry, and compare these results to theoretical modeling using density functional theory (DFT). Both methods consistently reveal that uniaxial stress induces changes of the nonlinear optical susceptibility of certain tensor elements on the order of up to 1 pm/(V GPa). The exact value depends on the tensor element that is addressed in our SHG analysis, on the crystal orientation, and also whether using compressive or tensile stresses. Furthermore, a lowering of the crystal symmetry when applying stress along the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mi>x</a:mi></a:math> or <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:mi>y</b:mi></b:math> crystallographic axes is observed by the appearance of new nonlinear optical tensor elements within the strained crystals.}},
  author       = {{Pionteck, Mike N. and Roeper, Matthias and Koppitz, Boris and Seddon, Samuel D. and Rüsing, Michael and Padberg, Laura and Eigner, Christof and Silberhorn, Christine and Sanna, Simone and Eng, Lukas M.}},
  issn         = {{2469-9950}},
  journal      = {{Physical Review B}},
  number       = {{6}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Second-order nonlinear piezo-optic properties of single crystal lithium niobate thin films}}},
  doi          = {{10.1103/physrevb.111.064109}},
  volume       = {{111}},
  year         = {{2025}},
}

@phdthesis{60286,
  author       = {{Austermeier, Laura}},
  title        = {{{Vorhersagemodell zum ortsaufgelösten Energieeintrag in dichtkämmenden Gleichdrall-Doppelschneckenextrudern}}},
  year         = {{2025}},
}

@phdthesis{60287,
  author       = {{Scholle, Maximilian}},
  title        = {{{Die verarbeitungsinduzierte Glasfaserschädigung von Bulk Molding Compounds}}},
  year         = {{2025}},
}

@article{60298,
  abstract     = {{In this work, we introduce PHOENIX, a highly optimized explicit open-source solver for two-dimensional nonlinear Schrödinger equations with extensions. The nonlinear Schrödinger equation and its extensions (Gross-Pitaevskii equation) are widely studied to model and analyze complex phenomena in fields such as optics, condensed matter physics, fluid dynamics, and plasma physics. It serves as a powerful tool for understanding nonlinear wave dynamics, soliton formation, and the interplay between nonlinearity, dispersion, and diffraction. By extending the nonlinear Schrödinger equation, various physical effects such as non-Hermiticity, spin-orbit interaction, and quantum optical aspects can be incorporated. PHOENIX is designed to accommodate a wide range of applications by a straightforward extendability without the need for user knowledge of computing architectures or performance optimization. The high performance and power efficiency of PHOENIX are demonstrated on a wide range of entry-class to high-end consumer and high-performance computing GPUs and CPUs. Compared to a more conventional MATLAB implementation, a speedup of up to three orders of magnitude and energy savings of up to 99.8% are achieved. The performance is compared to a performance model showing that PHOENIX performs close to the relevant performance bounds in many situations. The possibilities of PHOENIX are demonstrated with a range of practical examples from the realm of nonlinear (quantum) photonics in planar microresonators with active media including exciton-polariton condensates. Examples range from solutions on very large grids, the use of local optimization algorithms, to Monte Carlo ensemble evolutions with quantum noise enabling the tomography of the system's quantum state.}},
  author       = {{Wingenbach, Jan and Bauch, David and Ma, Xuekai and Schade, Robert and Plessl, Christian and Schumacher, Stefan}},
  issn         = {{0010-4655}},
  journal      = {{Computer Physics Communications}},
  publisher    = {{Elsevier BV}},
  title        = {{{PHOENIX – Paderborn highly optimized and energy efficient solver for two-dimensional nonlinear Schrödinger equations with integrated extensions}}},
  doi          = {{10.1016/j.cpc.2025.109689}},
  volume       = {{315}},
  year         = {{2025}},
}

@article{60565,
  author       = {{Bocchini, Adriana and Gerstmann, Uwe and Schmidt, Wolf Gero}},
  issn         = {{2469-9950}},
  journal      = {{Physical Review B}},
  number       = {{10}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Microscopic origin of gray tracks in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>KTiOPO</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:math>}}},
  doi          = {{10.1103/physrevb.111.104103}},
  volume       = {{111}},
  year         = {{2025}},
}

@article{60580,
  abstract     = {{<jats:title>Abstract</jats:title><jats:p>AlInP (001) is widely utilized as a window layer in optoelectronic devices, including world‐record III‐V multi‐junction solar cells and photoelectrochemical (PEC) cells. The chemical and electronic properties of AlInP (001) depend on its surface reconstruction, which impacts its interaction with electrolytes in PEC applications and passivation layers. This study investigates AlInP (001) surface reconstructions using density functional theory and experimental methods. Phosphorus‐rich (P‐rich) and indium‐rich (In‐rich) AlInP surfaces are prepared with in situ monitoring of the process by reflection anisotropy (RA) spectroscopy and confirmed by low‐energy electron diffraction and photoemission spectroscopy. The experimental RA spectra closely match the theoretical predictions obtained by solving the Bethe–Salpeter equation. It is shown that missing hydrogen on P‐rich surfaces and formation of In–In 1D atomic chains on In‐rich surfaces introduce mid‐gap surface states that pin the Fermi level and induce band bending. Time‐resolved two‐photon photoemission measurements reveal ultrafast near‐surface electron dynamics for both P‐rich and In‐rich surfaces, demonstrating photoexcited electrons reaching the surface conduction band minimum and relaxing to mid‐gap surface states on about hundreds of fs. This work provides the most extensive AlInP surface analysis to date, allowing for more targeted surface and interface engineering, which is crucial for the optimization and design of III‐V heterostructures.</jats:p>}},
  author       = {{Zare Pour, Mohammad Amin and Shekarabi, Sahar and Ruiz Alvarado, Isaac Azahel and Diederich, Jonathan and Gao, Yuyings and Paszuk, Agnieszka and Moritz, Dominik C. and Jaegermann, Wolfram and Friedrich, Dennis and van de Krol, Roel and Schmidt, Wolf Gero and Hannappel, Thomas}},
  issn         = {{1616-301X}},
  journal      = {{Advanced Functional Materials}},
  publisher    = {{Wiley}},
  title        = {{{Exploring Electronic States and Ultrafast Electron Dynamics in AlInP Window Layers: The Role of Surface Reconstruction}}},
  doi          = {{10.1002/adfm.202423702}},
  year         = {{2025}},
}

@article{58642,
  abstract     = {{We present a cost-effective self-assembly method to fabricate low-density dimer NPs in an NPoM architecture, using the M13 phage as a spacer layer. This will enable the development of dynamic plasmonic devices and advanced sensing applications.}},
  author       = {{Devaraj, Vasanthan and Ruiz Alvarado, Isaac Azahel and Lee, Jong-Min and Oh, Jin-Woo and Gerstmann, Uwe and Schmidt, Wolf Gero and Zentgraf, Thomas}},
  issn         = {{2055-6756}},
  journal      = {{Nanoscale Horizons}},
  pages        = {{537--548}},
  publisher    = {{Royal Society of Chemistry (RSC)}},
  title        = {{{Self-assembly of isolated plasmonic dimers with sub-5 nm gaps on a metallic mirror}}},
  doi          = {{10.1039/d4nh00546e}},
  volume       = {{10}},
  year         = {{2025}},
}

@inproceedings{60587,
  author       = {{Schapeler, Timon and Schlue, Fabian and Stefszky, Michael and Brecht, Benjamin and Silberhorn, Christine and Bartley, Tim}},
  booktitle    = {{Advanced Photon Counting Techniques XIX}},
  editor       = {{Itzler, Mark A. and McIntosh, K. Alex and Bienfang, Joshua C.}},
  publisher    = {{SPIE}},
  title        = {{{Optimizing photon-number resolution with superconducting nanowire multi-photon detectors}}},
  doi          = {{10.1117/12.3054905}},
  year         = {{2025}},
}