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This article presents a general way to enable automatic generation of digitized laboratories (a sort of digital twin for laboratory experimental setups) from remote laboratories and their easy deployment and publication. To demonstrate its effectiveness, we use two existing tools to generate and publish two digitized laboratories online from two implementations of a Snell's law remote laboratory, although they could be applied to many other remote laboratories. The first of these tools is a communication protocol that was designed to manipulate laboratory equipment through the Internet. This protocol can be used to automatically loop through different possible laboratory states and store them. The second one is a web platform that allows uploading files, that contain data sets of the laboratory states, to publish the digitized laboratory as a web application that is generated automatically.

The iLabs platform – a low cost, highly scalable way to provide online learning for remote and virtual laboratory experiments is introduced into a classroom setting for the first time. As the COVID-19 pandemic has disrupted conventional laboratory experiment-based teaching, the iLabs platform can be a potential solution to include remote and virtual experiments in the curricula. As a case study, the process and challenges of integrating an iLabs experiment into a course are discussed. The described process includes converting a physical experiment into an iLabs experiment and using it as a teaching tool in one course at Stanford University during the Autumn 2020-2021 quarter. Feedback collected from the students is discussed. Although performed on a small scale, the case study suggests that the platform has the potential to be a helpful teaching tool for science and technology classes. In addition to being a substitute for a physical laboratory during the pandemic, the platform can be included as a supplementary teaching tool complementing physical laboratory experiments after the pandemic as well and will aid remote education.

We present a computer-aided design tool for ion optical devices using the adjoint variable method. Numerical methods have been essential for the development of ion optical devices such as electron microscopes and mass spectrometers. Yet, the detailed computational analysis and optimization of ion optical devices is still onerous, since the governing equations of charged particle optics cannot be solved in closed form. Here, we show how to employ the adjoint variable method on the finite-element method and Störmer-Verlet method for electrostatic charged particle devices. This method allows for a full sensitivity analysis of ion optical devices, providing a quantitative measure of the effects of design parameters to device performance, at near constant computational cost with respect to the number of parameters. To demonstrate this, we perform such a sensitivity analysis for different freeform N-element Einzel lens systems including designs with over 13,000 parameters. We further show the optimization of the spot size of such lenses using a gradient-based method in combination with the adjoint variable method. The computational efficiency of the method facilitates the optimization of shapes and applied voltages of all surfaces of the device.

Reasoning about unexpected outcomes is crucial to scientific exploration and STEM education. To stimulate conversations about these outcomes, we integrated noise characteristics and uncertainty into the framework of Massively Scalable Online Laboratories (MSOLs), which provide a collaborative and interactive online environment for education. The MSOL approach reduces a physical experiment to a set of states and displays it in an interactive environment. With the approach described here, those stages exhibit noise characteristics and nondeterministic outcomes. As a demonstration, we successfully recorded and displayed an example experiment, which contains quantum noise and limited repeatability. We thus display experiments more realistically and lead students towards a deeper understanding of the physical reality by evoking their curiosity about the variation of the displayed outcomes.

Educating peers and broader audiences is of great significance within the scientific community. The education process aids the communication of ideas and allows for engagement with science. We present a ready-to-use tool to exchange data collected in laboratories in a scalable, graphical and easily accessible manner using Massively Scalable Online Laboratories (MSOL) embedded within Virtual Interactive Scalable Online Notebooks for Science (VISONS). The tool we present replicates the experiment in a visual and interactive way, dynamically displaying the experiment in all of its states. Using VISONS, researchers can more easily engage in discussions about their experimental results, which allows for a deeper understanding of their data and scientific challenges. The form of data exchange and graphic interface we present here helps to stimulate purposeful conversations about cutting-edge science by using VISONS during discussions with peers or in publications. Moreover, our approach, which uses efficient data storage and retrieval capabilities, provides scalable data management that laboratory environments currently lack. Simultaneously, we provide a more effective way for researchers manage their own work. VISONS offer a clear and concise version control system, assisting scientists at all stages of the development process. To provide information security during preliminary experimental work, before official publications, we incorporated a feature to choose the target audience for each experiment. To demonstrate the merits of VISONS, we recorded different versions of a cutting-edge science experiment, a quantum-noise limited differential phase contrast X-Ray imaging system, during its development process.

This Letter covers the design and implementation of a generalizable system for the precise alignment of X-ray gratings. Next-generation high-energy grating-based Differential Phase Contrast (gDPC) X-ray imaging systems require precise alignment of the X-ray gratings as low as 1 mrad in rotation and 0.5 mm in translation. In this work, we designed holographic fiducial marks, consisting of four reflective Fresnel zone plates, each placed in a separate quadrant of the mark. When illuminated with a collimated laser beam, each mark creates a predefined pattern of four points, which changes quantitatively for any misalignment in each of the three translational and three rotational degrees of freedom. We fabricated the designed fiducial marks using photolithography and etching processes. The experimental system is implemented using a HeNe laser and an optical imaging system, which includes a beam expander, a plate beam splitter, and a CMOS camera, suitable for aligning practical gratings in gDPC X-ray imaging systems. Our experimental results demonstrate the rotational precision capabilities of the reported alignment system down to 0.42 mrad around the optical axis and 0.03 mrad around the axes perpendicular to the optical axis. The translational precision of 83.64 μ m along the optical axis and 1.22 μ m along the axes perpendicular to the optical axis is also demonstrated.This Letter covers the design and implementation of a generalizable system for the precise alignment of X-ray gratings. Next-generation high-energy grating-based Differential Phase Contrast (gDPC) X-ray imaging systems require precise alignment of the X-ray gratings as low as 1 mrad in rotation and 0.5 mm in translation. In this work, we designed holographic fiducial marks, consisting of four reflective Fresnel zone plates, each placed in a separate quadrant of the mark. When illuminated with a collimated laser beam, each mark creates a predefined pattern of four points, which changes quantitatively for any misalignment in each of the three translational and three rotational degrees of freedom. We fabricated the designed fiducial marks using photolithography and etching processes. The experimental system is implemented using a HeNe laser and an optical imaging system, which includes a beam expander, a plate beam splitter, and a CMOS camera, suitable for aligning practical gratings in gDPC X-ray ...

Zusammenfassung Wir präsentieren eine Plattformtechnologie zur gleichzeitigen, mobilen, markerfreien Detektion von mehreren Proteinen. Ein photonischer Kristall, der mit Liganden lokal funktionalisiert ist, dient hier als Sensor. Über ein kompaktes, Kamera-basiertes Messsystem wird die Proteinanbindung an die Sensoroberfläche in ein Intensitätssignal umgewandelt, über dessen Amplitude die Proteinkonzentration bestimmt werden kann. Um das Detektionslimit dieser Technologie weiter zu verbessern, werden hier photonische Kristalle mit einer multiperiodischen und aperiodischen Gitterstruktur simulativ und experimentell untersucht. Dafür werden die Gesamtempfindlichkeit und die Resonanzgüte jeder Struktur bestimmt und mit der bisher verwendeten monoperiodischen Struktur verglichen. Es konnte festgestellt werde, dass sich die Resonanzgüte von mono- über multi- bis aperiodisch deutlich verbessert. Eine Steigerung der Gesamtempfindlichkeit konnte nicht festgestellt werden. Jedoch konnte anhand von Analysen der elektrischen Feldverteilung innerhalb der verschiedenen Strukturen beobachtet werden, dass die Modenausbreitungen in den aperiodischen Strukturen stark lokalisiert wird und die elektrische Feldintensität in diesen „Hot-Spots“ deutlich über der mittleren Feldintensität, die eine flächige Funktionalisierung repräsentiert, liegt. Diese lokale Resonanzausbildung konnte zudem bereits in ersten experimentellen Untersuchungen bestätigt werden.

Nanostructured dielectric waveguides are of high interest for biosensing applications, light emitting devices as well as solar cells. Multiperiodic and aperiodic nanostructures allow for custom-designed spectral properties as well as near-field characteristics with localized modes [1-4]. Here, a comparison of experimental results and simulation results obtained with different simulation methods is presented. We fabricated and characterized multiperiodic nanostructured dielectric waveguides with two, three, and four compound grating periods as well as aperiodic nanostructured waveguides based on Rudin-Shapiro, Fibonacci, and Thue-Morse binary sequences. The near-field and far-field properties are calculated employing the finite-element method (FEM), the finite- difference time-domain (FDTD) method as well as a rigorous coupled wave algorithm (RCWA). References[1] S. V. Boriskina, A. Gopinath, L. Dal Negro, Optical gap formation and localization properties of optical modes in deterministic aperiodic photonic structures, Opt. Express 16, 18813, 2008[2] E. Maciá, Exploiting aperiodic designs in nanophotonic devices, Rep Prog Phys 75, 036502,2012[3] C. Kluge, J. Adam, N. Barié, P. J. Jakobs, M. Guttmann, M. Gerken, Multiperiodic nanostructuresfor photon control, Opt. Express 22, A1363-A1371, 2014[4] L. T. Neustock, S. Jahns, J. Adam, M. Gerken, Optical waveguides with compound grating nanostructures for refractive index sensing, J. of Sensors, 6174527, 2016

Photonic waveguides with deterministic aperiodic corrugations offer rich spectral characteristics under surface-normal illumination. The finite-element method (FEM), the finite-difference time-domain (FDTD) method and a rigorous coupled wave algorithm (RCWA) are compared for computing the near-field and far-field properties of structures based on a Rudin-Shapiro binary sequence. All simulation methods predict multiple resonances with sensitivities in the range of 30 nm/RIU to 60 nm/RIU for bulk refractive index measurements. Local functionalization is estimated to improve the sensitivity for biomolecular binding by a factor of 2.97.

Wir prasentieren eine Plattformtechnologie zur mobilen, markerfreien Detektion von mehreren Proteinen gleichzeitig. Ein photonischer Kristall, der mit Liganden lokal funktionalisiert ist, dient hier als Sensor. Uber ein kompaktes, Kamera-basiertes Messsystem wird die Proteinanbindung an die Sensoroberflache in ein Intensitatssignal umgewandelt, uber dessen Amplitude die Proteinkonzentration bestimmt werden kann. Um die Detektionsgrenze dieser Technologie weiter zu verbessern, werden hier photonische Kristalle mit einer multiperiodischen und aperiodischen Gitterstruktur simulativ und experimentell untersucht. Dafur werden die Gesamtempfindlichkeit und die Resonanzgute jeder Struktur bestimmt und mit der bisher verwendeten monoperiodischen Struktur verglichen. Es konnte festgestellt werde, dass die Resonanzgute von monouber multibis aperiodisch sich deutlich verbessert. Eine Steigerung der Gesamtempfindlichkeit konnte nicht festgestellt werden. Jedoch konnte anhand von Analysen der elektrischen Feldverteilung innerhalb der verschiedenen Strukturen beobachtet werden, dass die Modenausbreitungen in den aperiodischen Strukturen stark lokalisiert wird und die Funktionalisierung reprasentiert, liegt. Diese lokale Resonanzausbildung konnte zudem bereits in ersten experimentellen Untersuchungen bestatigt werden.

Periodic dielectric photonic nanostructures have been used extensively as transducers in refractive index sensors. Photonic crystal slabs exhibit sharp resonances in the transmission and reflection spectrum. Changes in resonance wavelength, intensity, or quality factor are measured to monitor changes in the analyte region on top of the structure [1]. By specific biofunctionalization of the crystal surface, specific molecule capture is achieved. We demonstrated a handheld intensity-based measurement setup that allows for imaging detection of binding events at the surface [1]. To enhance the sensitivity of such systems, the use of deterministic aperiodic nanostructures (DANS) has been suggested [2-4]. DANS are engineered ordered nanostructures without periodicity [2,3]. The additional degrees of freedom allow for a tailoring of the optical properties. Boriskina et al. calculated that quasi-localized critical modes in aperiodic nanostructures simultaneously exhibit high quality factors Q und high sensitivity S to refractive index changes [2]. We previously calculated the spectral response of different DANS [4]. Here, we present experimental results for DANS devices (Thue- Morse, Fibonacci, Rudin-Shapiro) consisting of a nanoimprinted photo mold layer providing the nanostructure and a TiO2 high index layer (fig. 1). The measured characteristics (band diagram, far field) of these devices are compared to the ones of mono- and multiperiodic nanostructures. Near-field and far-field calculations are carried out for these structures and are compared to the experimental results.[1] Jahns, S., Bräu, M., Meyer, B. O., Karrock, T., Gutekunst, S. B., Blohm, L., Selhuber-Unkel, C., Buhmann, R., Nazirizadeh, Y., Gerken, M. (2015). Handheld imaging photonic crystal biosensor for multiplexed, label-free protein detection. Biomedical Optics Express, 6(10), 3724-3736.[2] Boriskina, S. V., Dal Negro, L. (2008). Sensitive label-free biosensing using critical modes in aperiodic photonic structures. Optics Express, 16(17), 12511-12522.[3] Dal Negro, L., Boriskina, S. V. (2012). Deterministic aperiodic anostructures for photonics and plasmonics applications. Laser and Photonics Reviews, 6(2), 178-218.[4] Neustock, L. T., Jahns, S., Adam, J., Gerken, M. (2016). Optical waveguides with compound multiperiodic grating nanostructures for refractive index sensing. Journal of Sensors, 501, 6174527.

A computationally efficient method for identifying the parameters of the Jiles-Atherton hysteresis model is presented. Adjoint analysis is used in conjecture with an accelerated gradient descent optimization algorithm. The proposed method is used to estimate the Jiles-Atherton model parameters of two different materials. The obtained results are found to be in good agreement with the reported values. By comparing with existing methods of model parameter estimation, the proposed method is found to be computationally efficient and fast converging.

Planar nanostructures allow for extraction of guided modes to increase the organic light-emitting diode (OLED) efficiency. In contrast to the typically employed nanostructures with one dominant space frequency, multi-periodic photonic crystals scatter a guided mode into multiple directions and thereby extend the design space for OLED outcoupling significantly. We present photoluminescence measurements of multi-periodic photonic crystals, obtained by superposition of multiple binary gratings, in an organic emitter layer. Together with transfer matrix and rigorous coupled wave analysis (RCWA) simulations, we show that the wavelength-dependent absorption in the waveguide material strongly affects the outcoupling intensity. In addition, RCWA simulations of the individual orders' intensities are shown to be in agreement with experimental data. Due to the broad spectral emission of OLEDs, RCWA can therefore be a valuable tool to design the guided mode scattering in a broad wavelength region. Potential applications include outcoupling-enhanced OLEDs with reduced angular color change.