@article{32148,
  author       = {{Gao, Xinghui and Hu, Wei and Schumacher, Stefan and Ma, Xuekai}},
  issn         = {{0146-9592}},
  journal      = {{Optics Letters}},
  keywords     = {{Atomic and Molecular Physics, and Optics}},
  number       = {{13}},
  pages        = {{3235--3238}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{Unidirectional vortex waveguides and multistable vortex pairs in polariton condensates}}},
  doi          = {{10.1364/ol.457724}},
  volume       = {{47}},
  year         = {{2022}},
}

@inbook{30288,
  abstract     = {{Lithium niobate (LiNbO3), a material frequently used in optical applications, hosts different kinds of polarons that significantly affect many of its physical properties. In this study, a variety of electron polarons, namely free, bound, and bipolarons, are analyzed using first-principles calculations. We perform a full structural optimization based on density-functional theory for selected intrinsic defects with special attention to the role of symmetry-breaking distortions that lower the total energy. The cations hosting the various polarons relax to a different degree, with a larger relaxation corresponding to a larger gap between the defect level and the conduction-band edge. The projected density of states reveals that the polaron states are formerly empty Nb 4d states lowered into the band gap. Optical absorption spectra are derived within the independent-particle approximation, corrected by the GW approximation that yields a wider band gap and by including excitonic effects within the Bethe-Salpeter equation. Comparing the calculated spectra with the density of states, we find that the defect peak observed in the optical absorption stems from transitions between the defect level and a continuum of empty Nb 4d states. Signatures of polarons are further analyzed in the reflectivity and other experimentally measurable optical coefficients.}},
  author       = {{Schmidt, Falko and Kozub, Agnieszka L. and Gerstmann, Uwe and Schmidt, Wolf Gero and Schindlmayr, Arno}},
  booktitle    = {{New Trends in Lithium Niobate: From Bulk to Nanocrystals}},
  editor       = {{Corradi, Gábor and Kovács, László}},
  isbn         = {{978-3-0365-3340-7}},
  pages        = {{231--248}},
  publisher    = {{MDPI}},
  title        = {{{Electron polarons in lithium niobate: Charge localization, lattice deformation, and optical response}}},
  doi          = {{10.3390/books978-3-0365-3339-1}},
  year         = {{2022}},
}

@inproceedings{35830,
  author       = {{Elsner, Julia and Tenberge, Claudia and Fechner, Sabine}},
  booktitle    = {{Fostering scientific citizenship in an uncertain world (Proceedings of ESERA 2021)}},
  editor       = {{Carvalho, Graça S. and Afonso, Ana Sofia and Anastácio, Zélia}},
  pages        = {{1241--1249}},
  publisher    = {{CIEC, University of Minho}},
  title        = {{{Modeling-based learning about chemical phenomena in primary education}}},
  year         = {{2022}},
}

@inproceedings{41800,
  author       = {{Sartison, M and  Camacho Ibarra, O and Jöns, Klaus D. and Caltzidis, I and Reuter, Dirk}},
  title        = {{{Scalable integration of quantum emitters into photonic integrated circuits}}},
  doi          = {{https://doi.org/10.1088/2633-4356/ac6f3e}},
  volume       = {{2}},
  year         = {{2022}},
}

@article{40371,
  abstract     = {{<jats:p>Multimode integrated interferometers have great potential for both spectral engineering and metrological applications. However, the material dispersion of integrated platforms constitutes an obstacle that limits the performance and precision of such interferometers. At the same time, two-colour nonlinear interferometers present an important tool for metrological applications, when measurements in a certain frequency range are difficult. In this manuscript, we theoretically developed and investigated an integrated multimode two-colour SU(1,1) interferometer operating in a supersensitive mode. By ensuring the proper design of the integrated platform, we suppressed the dispersion, thereby significantly increasing the visibility of the interference pattern. The use of a continuous wave pump laser provided the symmetry between the spectral shapes of the signal and idler photons concerning half the pump frequency, despite different photon colours. We demonstrate that such an interferometer overcomes the classical phase sensitivity limit for wide parametric gain ranges, when up to 3×104 photons are generated.</jats:p>}},
  author       = {{Ferreri, Alessandro and Sharapova, Polina R.}},
  issn         = {{2073-8994}},
  journal      = {{Symmetry}},
  keywords     = {{Physics and Astronomy (miscellaneous), General Mathematics, Chemistry (miscellaneous), Computer Science (miscellaneous)}},
  number       = {{3}},
  publisher    = {{MDPI AG}},
  title        = {{{Two-Colour Spectrally Multimode Integrated SU(1,1) Interferometer}}},
  doi          = {{10.3390/sym14030552}},
  volume       = {{14}},
  year         = {{2022}},
}

@article{30210,
  abstract     = {{Lithium niobate on insulator (LNOI) has a great potential for photonic integrated circuits, providing substantial versatility in design of various integrated components. To properly use these components in the implementation of different quantum protocols, photons with different properties are required. In this paper, we theoretically demonstrate a flexible source of correlated photons built on the LNOI waveguide of a special geometry. This source is based on the parametric down-conversion (PDC) process, in which the signal and idler photons are generated at the telecom wavelength and have different spatial profiles and polarizations, but the same group velocities. Distinguishability in polarizations and spatial profiles facilitates the routing and manipulating individual photons, while the equality of their group velocities leads to the absence of temporal walk-off between photons. We show how the spectral properties of the generated photons and the number of their frequency modes can be controlled depending on the pump characteristics and the waveguide length. Finally, we discuss special regimes, in which narrowband light with strong frequency correlations and polarization-entangled Bell states are generated at the telecom wavelength.}},
  author       = {{Ebers, Lena and Ferreri, Alessandro and Hammer, Manfred and Albert, Maximilian and Meier, Cedrik and Förstner, Jens and Sharapova, Polina R.}},
  issn         = {{2515-7647}},
  journal      = {{Journal of Physics: Photonics}},
  keywords     = {{tet_topic_waveguide}},
  pages        = {{025001}},
  publisher    = {{IOP Publishing}},
  title        = {{{Flexible source of correlated photons based on LNOI rib waveguides}}},
  doi          = {{10.1088/2515-7647/ac5a5b}},
  volume       = {{4}},
  year         = {{2022}},
}

@article{33670,
  author       = {{Schapeler, Timon and Bartley, Tim}},
  issn         = {{2469-9926}},
  journal      = {{Physical Review A}},
  number       = {{1}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Information extraction in photon-counting experiments}}},
  doi          = {{10.1103/physreva.106.013701}},
  volume       = {{106}},
  year         = {{2022}},
}

@inproceedings{63039,
  abstract     = {{<jats:p>We report on coherent transmission of beyond 100 GBd signaling based on plasmonic technology. Using dual-drive plasmonic-organic-hybrid I/Q modulator on silicon photonics platform, we demonstrate the successful transmission of 160-GBaud QPSK and 140-GBaud 16QAM modulations.</jats:p>}},
  author       = {{Mardoyan, Haïk and Jorge, Filipe and Destraz, Marcel and Duval, Bernadette and Bitachon, Bertold and Horst, Yannik and Benyahya, Kaoutar and Blache, Fabrice and Goix, Michel and De Leo, Eva and Habegger, Patrick and Meier, Norbert and Del Medico, Nino and Tedaldi, Valentino and Funck, Christian and Güsken, Nicholas Alexander and Leuthold, Juerg and Renaudier, Jéremie and Hoessbacher, Claudia and Heni, Wolfgang and Baeuerle, Benedikt}},
  booktitle    = {{Optical Fiber Communication Conference (OFC) 2022}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{Generation and transmission of 160-Gbaud QPSK Coherent Signals using a Dual-Drive Plasmonic-Organic Hybrid I/Q modulator on Silicon Photonics}}},
  doi          = {{10.1364/ofc.2022.th1j.5}},
  year         = {{2022}},
}

@inproceedings{63041,
  author       = {{Güsken, Nicholas Alexander}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{Plasmonic PICs—Terabit Modulation on the Micrometer Scale}}},
  doi          = {{https://opg.optica.org/abstract.cfm?URI=ECEOC-2022-Tu4E.3}},
  year         = {{2022}},
}

@article{30921,
  abstract     = {{Quantum walks function as essential means to implement quantum simulators, allowing one to study complex and often directly inaccessible quantum processes in controllable systems. In this contribution, the notion of a driven Gaussian quantum walk is introduced. In contrast to typically considered quantum walks in optical settings, we describe the operation of the walk in terms of a nonlinear map rather than a unitary operation, e.g., by replacing a beam-splitter-type coin with a two-mode squeezer, being a process that is controlled and driven by a pump field. This opens previously unattainable possibilities for quantum walks that include nonlinear elements as core components of their operation, vastly extending their range of applications. A full framework for driven Gaussian quantum walks is developed, including methods to dynamically characterize nonlinear, quantum, and quantum-nonlinear effects. Moreover, driven Gaussian quantum walks are compared with their classically interfering and linear counterparts, which are based on classical coherence of light rather than quantum superpositions. In particular, the generation and boost of highly multimode entanglement, squeezing, and other quantum effects are studied over the duration of the nonlinear walk. Importantly, we prove the quantumness of the evolution itself, regardless of the input state. A scheme for an experimental realization is proposed. Furthermore, nonlinear properties of driven Gaussian quantum walks are explored, such as amplification that leads to an ever increasing number of correlated quantum particles, constituting a source of new walkers during the walk. Therefore, a concept for quantum walks is proposed that leads to—and even produces—directly accessible quantum phenomena, and that renders the quantum simulation of nonlinear processes possible.}},
  author       = {{Held, Philip and Engelkemeier, Melanie and De, Syamsundar and Barkhofen, Sonja and Sperling, Jan and Silberhorn, Christine}},
  issn         = {{2469-9926}},
  journal      = {{Physical Review A}},
  number       = {{4}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Driven Gaussian quantum walks}}},
  doi          = {{10.1103/physreva.105.042210}},
  volume       = {{105}},
  year         = {{2022}},
}

@inproceedings{35838,
  author       = {{Hörnlein, Madeleine and Kulgemeyer, Christoph}},
  location     = {{Aachen}},
  title        = {{{Wie können Erklärvideos zum Erwerb physikalischen Konzeptwissens beitragen? }}},
  year         = {{2022}},
}

@article{35760,
  author       = {{Kulgemeyer, Christoph and Hörnlein, Madeleine and Sterzing, Fabian Gabriel}},
  issn         = {{0950-0693}},
  journal      = {{International Journal of Science Education}},
  keywords     = {{Education}},
  number       = {{11}},
  pages        = {{1855--1875}},
  publisher    = {{Informa UK Limited}},
  title        = {{{Exploring the effects of physics explainer videos and written explanations on declarative knowledge and the illusion of understanding}}},
  doi          = {{10.1080/09500693.2022.2100507}},
  volume       = {{44}},
  year         = {{2022}},
}

@article{63508,
  abstract     = {{<jats:title>Abstract</jats:title><jats:p>Tailored nanoscale quantum light sources, matching the specific needs of use cases, are crucial building blocks for photonic quantum technologies. Several different approaches to realize solid-state quantum emitters with high performance have been pursued and different concepts for energy tuning have been established. However, the properties of the emitted photons are always defined by the individual quantum emitter and can therefore not be controlled with full flexibility. Here we introduce an all-optical nonlinear method to tailor and control the single photon emission. We demonstrate a laser-controlled down-conversion process from an excited state of a semiconductor quantum three-level system. Based on this concept, we realize energy tuning and polarization control of the single photon emission with a control-laser field. Our results mark an important step towards tailored single photon emission from a photonic quantum system based on quantum optical principles.</jats:p>}},
  author       = {{Jonas, B. and Heinze, D. and Schöll, E. and Kallert, P. and Langer, T. and Krehs, S. and Widhalm, A. and Jöns, K. D. and Reuter, D. and Schumacher, S. and Zrenner, A.}},
  issn         = {{2041-1723}},
  journal      = {{Nature Communications}},
  number       = {{1}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Nonlinear down-conversion in a single quantum dot}}},
  doi          = {{10.1038/s41467-022-28993-3}},
  volume       = {{13}},
  year         = {{2022}},
}

@article{25605,
  abstract     = {{The nonlinear process of second harmonic generation (SHG) in monolayer (1L) transition metal dichalcogenides (TMD), like WS2, strongly depends on the polarization state of the excitation light. By combination of plasmonic nanostructures with 1L-WS2 by transferring it onto a plasmonic nanoantenna array, a hybrid metasurface is realized impacting the polarization dependency of its SHG. Here, we investigate how plasmonic dipole resonances affect the process of SHG in plasmonic–TMD hybrid metasurfaces by nonlinear spectroscopy. We show that the polarization dependency is affected by the lattice structure of plasmonic nanoantenna arrays as well as by the relative orientation between the 1L-WS2 and the individual plasmonic nanoantennas. In addition, such hybrid metasurfaces show SHG in polarization states, where SHG is usually forbidden for either 1L-WS2 or plasmonic nanoantennas. By comparing the SHG in these channels with the SHG generated by the hybrid metasurface components, we detect an enhancement of the SHG signal by a factor of more than 40. Meanwhile, an attenuation of the SHG signal in usually allowed polarization states is observed. Our study provides valuable insight into hybrid systems where symmetries strongly affect the SHG and enable tailored SHG in 1L-WS2 for future applications.}},
  author       = {{Spreyer, Florian and Ruppert, Claudia and Georgi, Philip and Zentgraf, Thomas}},
  issn         = {{1936-0851}},
  journal      = {{ACS Nano}},
  number       = {{10}},
  pages        = {{16719--16728}},
  title        = {{{Influence of Plasmon Resonances and Symmetry Effects on Second Harmonic Generation in WS2–Plasmonic Hybrid Metasurfaces}}},
  doi          = {{10.1021/acsnano.1c06693}},
  volume       = {{15}},
  year         = {{2021}},
}

@article{26039,
  author       = {{Lahme, Simon and Bauer, Anna and Reinhold, Peter}},
  journal      = {{Phydid B, Didaktik der Physik, Beiträge zur DPG-Frühjahrstagung}},
  pages        = {{127--134}},
  title        = {{{Ansätze zur Diagnose und Förderung von Problemlösefähigkeiten in der Studieneingangsphase Physik}}},
  year         = {{2021}},
}

@article{21125,
  author       = {{Kismann, Michael and Riedl, Dr. Thomas and Lindner, Prof. Dr. Jörg KN}},
  journal      = {{Materials Science in Semiconductor Processing}},
  title        = {{{Ordered arrays of Si nanopillars with alternating diameters fabricated by nanosphere lithography and metal-assisted chemical etching}}},
  year         = {{2021}},
}

@article{21374,
  abstract     = {{<jats:p>A dark-field scanning transmission ion microscopy detector was designed for the helium ion microscope. The detection principle is based on a secondary electron conversion holder with an exchangeable aperture strip allowing its acceptance angle to be tuned from 3 to 98 mrad. The contrast mechanism and performance were investigated using freestanding nanometer-thin carbon membranes. The results demonstrate that the detector can be optimized either for most efficient signal collection or for maximum image contrast. The designed setup allows for the imaging of thin low-density materials that otherwise provide little signal or contrast and for a clear end-point detection in the fabrication of nanopores. In addition, the detector is able to determine the thickness of membranes with sub-nanometer precision by quantitatively evaluating the image signal and comparing the results with Monte Carlo simulations. The thickness determined by the dark-field transmission detector is compared to X-ray photoelectron spectroscopy and energy-filtered transmission electron microscopy measurements.</jats:p>}},
  author       = {{Emmrich, Daniel and Wolff, Annalena and Meyerbröker, Nikolaus and Lindner, Jörg and Beyer, André and Gölzhäuser, Armin}},
  issn         = {{2190-4286}},
  journal      = {{Beilstein Journal of Nanotechnology}},
  pages        = {{222--231}},
  title        = {{{Scanning transmission helium ion microscopy on carbon nanomembranes}}},
  doi          = {{10.3762/bjnano.12.18}},
  year         = {{2021}},
}

@article{21631,
  abstract     = {{<jats:p>Secret sharing is a well-established cryptographic primitive for storing highly sensitive information like encryption keys for encoded data. It describes the problem of splitting a secret into different shares, without revealing any information to its shareholders. Here, we demonstrate an all-optical solution for secret sharing based on metasurface holography. In our concept, metasurface holograms are used as spatially separable shares that carry encrypted messages in the form of holographic images. Two of these shares can be recombined by bringing them close together. Light passing through this stack of metasurfaces accumulates the phase shift of both holograms and optically reconstructs the secret with high fidelity. In addition, the hologram generated by each single metasurface can uniquely identify its shareholder. Furthermore, we demonstrate that the inherent translational alignment sensitivity between two stacked metasurface holograms can be used for spatial multiplexing, which can be further extended to realize optical rulers.</jats:p>}},
  author       = {{Georgi, Philip and Wei, Qunshuo and Sain, Basudeb and Schlickriede, Christian and Wang, Yongtian and Huang, Lingling and Zentgraf, Thomas}},
  issn         = {{2375-2548}},
  journal      = {{Science Advances}},
  number       = {{16}},
  title        = {{{Optical secret sharing with cascaded metasurface holography}}},
  doi          = {{10.1126/sciadv.abf9718}},
  volume       = {{7}},
  year         = {{2021}},
}

@article{23815,
  abstract     = {{In this paper, silicon oxynitride films (SiON) grown by plasma-enhanced chemical vapor deposition are investigated. As precursor gases silane (SiH4), nitrous oxide (N2O), nitrogen (N2) and ammonia (NH3) are used with different compositions. We find that for achieving high nitrogen content adding ammonia to the precursor mix is most efficient. Moreover, we investigate the balance between adsorption and desorption processes during film growth by investigating the film growth rate as a function of the substrate temperature. From these data we are able to determine an effective activation energy for the film growth, corresponding to the difference between adsorption and desorption energy. Finally, we have thoroughly investigated the optical properties of the films using spectroscopic ellipsometry. From these measurements, we suggest a parametrized model for the refractive index and extinction coefficient in a wide range of compositions based on a Cauchy- and a Lorentz-fit.}},
  author       = {{Aschwanden, R. and Köthemann, R. and Albert, M. and Golla, C. and Meier, Cedrik}},
  issn         = {{0040-6090}},
  journal      = {{Thin Solid Films}},
  title        = {{{Optical properties of silicon oxynitride films grown by plasma-enhanced chemical vapor deposition}}},
  doi          = {{10.1016/j.tsf.2021.138887}},
  volume       = {{736}},
  year         = {{2021}},
}

@article{20900,
  author       = {{Albert, M. and Golla, C. and Meier, Cedrik}},
  issn         = {{0022-0248}},
  journal      = {{Journal of Crystal Growth}},
  title        = {{{Optical in-situ temperature management for high-quality ZnO molecular beam epitaxy}}},
  doi          = {{10.1016/j.jcrysgro.2020.126009}},
  volume       = {{557}},
  year         = {{2021}},
}