Schott AG

This letter demonstrates the use of structured-glass waveguide (SGW) technology in a stackable multilayer configuration in order to exhibit the versatile nature of structured-glass in high-frequency and high-performance applications. A novel multilayer corrugated elliptic horn antenna composed of nine wafer layers is designed for operation in the D-band frequency range and exhibits the use of a circular waveguide feed line. In this manner, the SGW antenna design is introduced to the literature for the first time and demonstrated with the highest operating frequency to date for structured-glass-based waveguide components. Detailed build profiles are provided with reference to the structured-glass fabrication method. Two of the proposed antenna components are fabricated in order to validate the gain measurement. The measured results are shown to achieve highly accurate S -parameter results and beam patterns throughout the selected frequency range.

Contemporary Li‐ion batteries are facing substantial challenges like safety and limited energy density. The development of all‐solid‐state battery cells mitigates safety hazards and allows the use of Li‐metal anodes increasing energy density. Garnet‐type solid electrolytes can be vital to achieving an all‐solid‐state cell and an understanding of the influence of its microstructure on the electrochemical performance is crucial for material and cell design. In this work the influence of grain size on the Li‐ion conductivity of Li7‐3xLa3Zr2AlxO12 (x=0.22) is presented. The synthesis and processing procedure allows changing the ceramic grain size, while maintaining the same synthesis parameters, eliminating influences of the synthesis on grain boundary composition. Field assisted sintering technology is a powerful method to obtain dense, fine‐grained ceramics with an optimal grain size of 2–3 μm, where the conductivity is double that of the counterpart (0.7 μm). A total Li‐ion conductivity of 0.43 mS cm⁻¹ and an activation energy of 0.36 eV were achieved. The oxide‐based all‐solid‐state battery cell combining the garnet‐type electrolyte, a Li‐metal anode and a thin‐film LiCoO2 cathode was assembled and cycled at room temperature for 90 hours. This represents a proof of concept, for the application of oxide‐based electrolytes at ambient temperatures.

Scattering luminescent materials dispersed in liquid and solid matrices and luminescent powders are increasingly relevant for fundamental research and industry. Examples are luminescent nano- and microparticles and phosphors of different compositions in various matrices or incorporated into ceramics with applications in energy conversion, solid-state lighting, medical diagnostics, and security barcoding. The key parameter to characterize the performance of these materials is the photoluminescence/fluorescence quantum yield (Φf), i.e., the number of emitted photons per number of absorbed photons. To identify and quantify the sources of uncertainty of absolute measurements of Φf of scattering samples, the first interlaboratory comparison (ILC) of three laboratories from academia and industry was performed by following identical measurement protocols. Thereby, two types of commercial stand-alone integrating sphere setups with different illumination and detection geometries were utilized for measuring the Φf of transparent and scattering dye solutions and solid phosphors, namely, YAG:Ce optoceramics of varying surface roughness, used as converter materials for blue light emitting diodes. Special emphasis was dedicated to the influence of the measurement geometry, the optical properties of the blank utilized to determine the number of photons of the incident excitation light absorbed by the sample, and the sample-specific surface roughness. While the Φf values of the liquid samples matched between instruments, Φf measurements of the optoceramics with different blanks revealed substantial differences. The ILC results underline the importance of the measurement geometry, sample position, and blank for reliable Φf data of scattering the YAG:Ce optoceramics, with the blank’s optical properties accounting for uncertainties exceeding 20%.

Introduction Medical syringes are widely used in hospitals to store and administer drugs, and the contact time between the drugs and these syringes can vary from a few minutes to several weeks like for pharmaceutical preparations. The aim of this comparative study was to evaluate the potential sorption phenomena occurring between three drugs (paracetamol, diazepam and insulin aspart) and polypropylene syringes (PP) or syringes made of Cyclic Olefin Copolymer (COC). Materials and methods 50 mL 3-part syringes made of either COC with crosslinked silicone on the barrel inner surface (COC-CLS) and a bromobutyl plunger seal, or PP lubricated with silicone oil (PP-SOL) with a polyisoprene plunger seal were used. Results COC-CLS syringes induced less sorption of diazepam and insulin than PP-SOL syringes and the plunger seal material seemed to be the main cause of these interactions. An alkalinization of the medications in contact with the PP-SOL syringes was observed. It could be caused by leachable compounds and should be investigated further. Conclusion This work shows once again that it is essential to consider content-container interactions to help improve the safe use of parenteral drugs.

Hybrid solid electrolytes (HSEs), namely mixtures of polymer and inorganic electrolytes, have supposedly improved properties with respect to inorganic and polymer electrolytes. In practice, HSEs often show ionic conductivity below expectations, as the high interface resistance limits the contribution of inorganic electrolyte particles to the charge transport process. In this study, the transport properties of a series of HSEs containing Li(1+x)AlxTi(2–x)(PO4)3 (LATP) as Li⁺‐conducting filler are analyzed. The occurrence of Li⁺ exchange across the two phases is proved by isotope exchange experiment, coupled with ⁶Li/⁷Li nuclear magnetic resonance (NMR), and by 2D ⁶Li exchange spectroscopy (EXSY), which gives a time constant for Li⁺ exchange of about 50 ms at 60 °C. Electrochemical impedance spectroscopy (EIS) distinguishes a short‐range and a long‐range conductivity, the latter decreasing with LATP concentration. LATP particles contribute to the overall conductivity only at high temperatures and at high LATP concentrations. Pulsed field gradient (PFG)‐NMR suggests a selective decrease of the anions’ diffusivity at high temperatures, translating into a marginal increase of the Li⁺ transference number. Although the transport properties are only marginally affected, addition of moderate amounts of LATP to polymer electrolytes enhances their mechanical properties, thus improving the plating/stripping performance and processability.

Three machine-learned potentials (SNAP, NNP, ACE) were created from the same training set of DFT energies and forces for a total of 1024 structures. DFT calculations were performed with the PBE functional and the Grimme D3 corrections. DFT energies can be reproduced within a few meV by the potentials. The potentials are evaluated how they predict structures, thermal expansion coefficients, and ionic conductivities of α- and β-eucryptite. Structures and thermal expansion coefficients are in good agreement with experimental values. All potentials reproduce the negative thermal expansion coefficient along the c axis of β-eucryptite, although only ACE calculates a negative thermal expansion coefficient for the volume. Ionic conductivities can be predicted only qualitatively correct. Molecular dynamics simulations performed with some of the potentials at higher temperatures can result in unphysical structures.

As the industrialization of waveguide based AR devices is progressing, considerations around design based shaping of waveguides as well as robustness move into focus. A promising approach for scalable free‐form cutting with high strength and precision is the utilization of ultrashort pulsed lasers. Various possible laser process parameters and different material compositions of high index glasses are challenging the optimization with respect to strength of the glass. SCHOTT AG and 3D‐Micromac AG optimized a separation process towards high and predictable bending strength and integrated it into a modular machine concept freely scalable from lab to mass production use.

Lithium metal-based solid-state batteries (SSBs) have attracted much attention due to their potentially higher energy densities and improved safety compared with lithium-ion batteries. One of the most promising solid electrolytes, garnet-type Li7La3Zr2O12 (LLZO), has been investigated intensively in recent years. It enables the use of a lithium metal anode, but its application is still challenging because of lithium dendrites that grow at voids, cracks, and grain boundaries of sintered bodies during cycling of the battery cell. In this work, glass-ceramic Ta-doped LLZO produced in a unique melting process was investigated. Upon cooling, an amorphous phase is generated intrinsically, whose composition and fraction are adjusted during the process. Herein, it was set to about 4 wt % containing Li2O and a Li2O-SiO2 phase. During sintering, it was shown to segregate into the grain boundaries and decrease porosity via liquid phase sintering. Sintering temperature and sintering time were found to be reduced compared with the LLZO fabricated by a solid-state reaction while maintaining high density and ionic conductivity. The glass-ceramic sintered at 1130 °C for 0.5 h showed a room-temperature ionic conductivity of 0.64 mS cm-1. Most importantly, the evenly distributed amorphous phase along the grain boundaries effectively hinders lithium dendrite growth. Besides mechanically blocking pores and voids, it helps to prevent inhomogeneous distribution of current density. The critical current density (CCD) of the Li|LLZTO|Li symmetric cell was determined as 1.15 mA cm-2, and in situ lithium plating experiments in a scanning electron microscope revealed superior dendrite stability properties. Therefore, this work provides a promising strategy to prepare a dense and dendrite-suppressing solid electrolyte for future implementation in SSBs.

Laser glass is a highly engineered optical material that enables the amplification of light in laser systems. It is known for being the heart of the largest laser facilities ever built, where thousands of neodymium-doped meter-sized slabs of laser glass create intense beams of near-infrared laser radiation used to study fusion reactions. Or if doped with ytterbium and erbium, laser glass can be made into millimeter-sized components empowering range-finders and dermatological lasers. Decades of development have poised laser glass for the next challenge on the horizon: amplifying light for sustainable inertial fusion energy power plants.

In many applications, the spatial refractive index variation – called homogeneity – within a measurement aperture either in one or two directions is important. Typical application examples are prisms in ultra-precision metrology with stability in multiple directions. Large lenses are used in artificial laser guide star systems for atmospheric correction in large telescopes. The challenge of enabling highest refractive index homogeneities requires tight control of all production steps from melting to hot forming and fine annealing. Large optical formats can be produced as singular castings in moulds up to 1.2 m in diameter and 250 mm thickness. Smaller formats are available as blocks produced in dimensions of approx. 250 x 250 x 180 mm3. A more economic and ecologic way is the production of continuous strips of glass up to approx. 500 mm width and 120 mm thickness. Recently SCHOTT has improved the homogeneity of these continuously produced jumbo strips significantly. Now homogeneity of up to H4 quality (2 ppm index maximum variation) can be provided on apertures up to approx. 900 mm x 500 mm. This paper gives an insight overview on the latest results and current state of this topic at the optical glass manufacturer SCHOTT.

A group of the DECHEMA working group “Single‐Use Technology in Biopharmaceutical Manufacture” is investigating the potential use of single‐use systems for cellular agricultural applications. The preliminary results are summarized in this article. In the biopharmaceutical industry, single‐use systems are well established alongside their reusable counterparts. The DECHEMA working group “Single‐Use Technology in Biopharmaceutical Manufacture” is currently investigating whether single‐use systems can also be used for cellular agricultural applications and preliminary results are presented.

Cutting glass to shape with ultra short laser pulses is nowadays a well established industrial process. Pulses with an elongated straight focal volume (line focus) are used to modify the workpiece throughout its entire depth with one single laser shot. At the same time, processed glass is often required to have a seamed or round edge, which usually requires an extra grinding step. Here we demonstrate that curved line foci can be used to combine cutting and edge shaping of glass sheets in one laser process. We reconsider the Airy-Gauss beam for this purpose, and suggest modifications to the beam profile to avoid unwanted effects, in particular an asymmetric laser modification of the glass sheet. We provide a combined experimental and numerical analysis of the laser process, and show a symmetric convex edge created in a 920μm thick glass sheet.