Material sciences

  • Safe energy transport made easy – Adaptive processing of complex control data

    Thermoplastic fiber-reinforced pipe.  Source: Fraunhofer IPT

    Pipes for the oil and gas industry which are used to transport raw materials from the seabed to the surface, have to meet specific requirements. They are highly relevant to security because every single pipe must be able to fully withstand the enormous loads of deep-sea production. Hence, controlling the manufacturing process of wound thermoplastic fiber-reinforced pipes is extremely complex. The EU research project “ambliFibre”, consisting of thirteen international partners led by the Aachen-based Fraunhofer Institute for Production Technology IPT, focuses on the manufacturing of these pipesand aims to develop an Industrie-4.0-compliant, highly flexible and reliable control system.

  • Saving Energy by Taking a Close Look Inside Transistors

    Physicist Martin Hauck fits a silicon carbide transistor into the measuring apparatus: researchers at FAU have discovered a method for finding defects at the interfaces of switches. FAU/Michael Krieger, Martin Hauck

     

    Transistors are needed wherever current flows, and they are an indispensable component of virtually all electronic switches. In the field of power electronics, transistors are used to switch large currents. However, one side-effect is that the components heat up and energy is lost as a result. One way of combating this and potentially making considerable savings is to use energy-efficient transistors. Researchers at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have developed a simple yet accurate method for finding defects in the latest generation of silicon carbide transistors. This will speed up the process of developing more energy-efficient transistors in future. They have now published their findings in the renowned journal Communications Physics.*

  • Scaling Silicon Quantum Photonics Technology

    A large-scale integrated silicon-photonic quantum circuit for controlling multidimensional entanglement. Graphic: from the original publication

    The realisation of controllable large quantum devices is key for the development of quantum technologies. Now a team of researchers from the University of Bristol, Peking University, Technical University of Denmark, ICFO Spain, PAS, University of Copenhagen and Dr. Jordi Tura from the Theory Division at the Max Planck Institute of Quantum Optics has developed a large-scale integrated silicon-photonics quantum circuit for the precise and general control of multidimensional entanglement.

  • Scanning Tunneling Microscopy Measurements Identify Active Sites on Catalysts

    The analysis of the tunneling currents of a scanning tunneling microscope reveal the active sites on the catalyst surface. Image: Christoph Hohmann / NIM

    Chemistry live: Using a scanning tunneling microscope, researchers at the Technical University of Munich (TUM) were able for the very first time to witness in detail the activity of catalysts during an electro-chemical reaction. The measurements show how the surface structure of the catalysts influences their activity. The new analysis method can now be used to improve catalysts for the electrochemical industry.

  • Scientists Develop Highly Sensitive Molecular Optical Pressure Sensor

    The molecular ruby in a solid (red) and dissolved (yellow) state can be used for contactless optical measurement of pressure. photo/©: Sven Otto, JGU

     

    Chemists at Johannes Gutenberg University Mainz (JGU) and at the Université de Montréal in Canada have developed a molecular system capable of very precise optical pressure measurements. The gemstone ruby served as the source of inspiration. However, the system developed by the team headed by Professor Katja Heinze at the JGU Institute of Inorganic Chemistry and Analytical Chemistry and Professor Christian Reber at the Université de Montréal is a water-soluble molecule, not an insoluble solid.

  • Scientists develop molecular thermometer for contactless measurement using infrared light

    The molecular ruby in a solid (red) and dissolved (yellow) state can be used for contactless measurement of temperature. photo/©: Sven Otto, JGU

    Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine.

    Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM) in Berlin have developed a molecular thermometer. The gemstone ruby served as the source of inspiration. However, the thermometer developed by the team headed by Professor Katja Heinze at the JGU Institute of Inorganic Chemistry and Analytical Chemistry is a water-soluble molecule, not an insoluble solid.

  • Scientists Shine New Light on the “Other High Temperature Superconductor”

    Intense laser pulses were used to photo-excite bismuthate compounds, in which “charge-density-waves” (left side) coexist with superconductivity (right side). Image: Joerg M. Harms, MPSD

    A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

  • Scientists shrink electron gun to matchbox size

    A miniature electron gun driven by Terahertz radiation: An ultraviolett pulse (blue) back-illuminates the gun photocathode, producing a high density electron bunch inside the gun. The bunch is immediately accelerated by ultra-intense single cycle Terahertz pulses to energies approaching one kilo-electronvolt (keV). These high-field optically-driven electron guns can be utilized for ultrafast electron diffraction or injected into the accelerators for X-ray light sources. Credit: W. Ronny Huang, CFEL/DESY/MIT

    Terahertz technology has the potential to enable new applications.In a multi-national effort, an interdisciplinary team of researchers from DESY and the Massachusetts Institute of Technology (MIT) has built a new kind of electron gun that is just about the size of a matchbox. Electron guns are used in science to generate high-quality beams of electrons for the investigation of various materials, from biomolecules to superconductors. They are also the electron source for linear particle accelerators driving X-ray free-electron lasers.

  • Self-disposing supramolecular materials with a tunable lifetime

    With the peptide-synthesizer Dr. Marta Tena-Solsona produces the building blocks for the gels she investigates. Photo: Uli Benz / TUM

    Materials that assemble themselves and then simply disappear at the end of their lifetime are quite common in nature. Researchers at the Technical University Munich (TUM) have now successfully developed supramolecular materials that disintegrate at a predetermined time – a feature that could be used in numerous applications. Plastic bottles, empty cans, old toys, torn T-shirts and worn-out mobile phones – day for day, mankind produces millions of tons of waste. How can we prevent our planet from stifling in the garbage?

  • Self-illuminating Pixels for a New Display Generation

    Brilliant colors – a researcher demonstrates the brightness of the light emitted by quantum dots. © Fraunhofer IAP, Photographer: Till Budde

    There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

  • Self-organizing Molecules: Cups with Attoliter Volume

    Stacked Janus nanocups, before being separated. University of Duisburg-Essen (UDE)

    They look like interlocking egg cups, but a hen's egg is 100,000 times as thick as one of the miniature cups: Scientists at the Center for Nanointegration (CENIDE) at the University of Duisburg-Essen (UDE) have made polymers to form themselves into tiny cups on their own. They could, for example, be used to remove oil residues from water. The scientists have published their results in the journal "Angewandte Chemie".

  • Setting New Standards in Solids Analysis

    The team grinds up samples of rocks and other materials to nano-sized particles, such as iron ore (photo). They can be used as reference materials for precise calibration of measuring devices. Simon Nordstad / Kiel University

    Young start-up team from Kiel University develops new reference materials for direct microanalysis of solids. How badly plants are affected by contaminated soil, what the sea floor can reveal about past climate periods, or what yield an ore mine could deliver in future - an analysis of the chemical composition of minerals and rocks can often provide valuable information. For accurate results, not only are high-quality measuring devices required, but also first-class reference materials, in order to be able to accurately calibrate the instruments.

  • Shedding light on light absorption: titanium dioxide unveiled

    Lattice structure of anatase TiO2 with a graphical representation of the 2D exciton that is generated by the absorption of light. This 2D exciton is the lowest energy excitation of the material.

    MPSD scientists have uncovered the hidden properties of titanium dioxide, one of the most promising materials for light-conversion technology. The anatase crystal form of Titanium dioxide (TiO₂) is one of the most promising materials for photovoltaic and photocatalytic applications nowadays. Despite years of studies on the conversion of light absorbed by anatase TiO₂, into electrical charges, the very nature of its fundamental electronic and optical properties remained still unknown. Scientists from the MPSD (Max Planck Institute for the Structure and Dynamics of Matter) at CFEL (Center for Free-Electron Laser Science) in Hamburg, together with their international partners at EPFL, Lausanne used a combination of cutting-edge steady-state and ultrafast spectroscopic techniques, as well as theoretical simulation tools to elucidate these fundamental properties of anatase TiO₂. Their work is published in Nature Communications.

  • Shedding Light on Weyl Fermions

    A wave of laser light hits the magnetic material, shaking the electron spins (arrows). This weakens magnetism and induces Weyl fermions in the laser-shaken material. Jörg Harms, MPSD

    Researchers from the Theory Department of the Max Planck Institute for Structure and Dynamics (MPSD) in Hamburg and North Carolina State University in the US have demonstrated that the long-sought magnetic Weyl semi-metallic state can be induced by ultrafast laser pulses in a three-dimensional class of magnetic materials dubbed pyrochlore iridates. Their results, which have now been published in Nature Communications, could enable high-speed magneto-optical topological switching devices for next-generation electronics.

  • Significantly more productivity in USP lasers

    With the hybrid systems composed of freely programmable multi-beam optics and galvo scanners, a laser beam can be split into any number of beamlets. © Fraunhofer ILT, Aachen, Germany / Volker Lannert.

    In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

  • Silicon as a New Storage Material for the Batteries of the Future

    An etching process gives the originally blank discs a porous surface - and a colourful sheen. The porous silicon layer can be bonded particularly well with a copper electrode. Photo: Siekmann, Kiel University

    Kiel University and equipment manufacturers RENA Technologies present new approach at the Hannover Messe. Longer life times, larger ranges and faster recharging - developments such as electric mobility or the miniaturisation of electronics require new storage materials for batteries. With its enormous storage capacity, silicon would potentially have decisive advantages over the materials used in commercial available lithium-ion batteries. But due to its mechanical instability, it has so far been almost impossible to use silicon for storage technology.

  • Silicon solar cell of ISFH yields 25% efficiency with passivating POLO contacts

    Monocrystalline 25%-silicon solar cell with POLO-contacts for both polarities on the rear side of the solar cell. ISFH

    The Lower Saxon‘ Institute for Solar Energy Research Hamelin (ISFH) achieved a solar cell efficiency of 25 % in collaboration with the Institute of Electronic Materials and Devices (MBE) of the Leibniz Universität Hannover. This high efficiency was accomplished with passivating "poly-Si on oxide" contacts (POLO) for both polarities, which avoid the otherwise high recombination beneath the metal contacts. The Lower Saxon‘ Institute for Solar Energy Research Hamelin (ISFH), an affiliated institute of the “Leibniz Universität Hannover” in collaboration with the Institute of Electronic Materials and Devices (MBE) of the “Leibniz Universität Hannover” achieved a solar cell efficiency of 25 %. This result was confirmed by DAkkS-accredited independent calibration laboratory ISFH CalTeC and presented at the Asian conference PVSEC-26 in Singapore.

  • Simulating cellular sorting processes

    Scientists synthesized four kinds of gel particles, which can co-assemble into different objects. The illustration visualizes this process using colored droplets. Andreas Walther, University of Freiburg

    A plant or an animal cell uses numerous processes to sort and assemble tiny building blocks into larger molecules, to rebuild molecules or to dissolve them. Using synthetic gel particles, scientists try to simulate these cellular procedures; however, mimicking the complexity of natural processes presents a formidable task for scientists. Researchers from the DWI – Leibniz Institute for Interactive Materials in Aachen and the University of Freiburg now developed a set of four different, micrometer-sized building blocks, which can self-sort and co-assemble into defined compositions and disassemble at the push of a button.

  • Single crystal growth in hot air: nice and easy

    Schematic of the growth setup. The desired single crystals grow from separated educts at 1020°C via vapor transport. The condensation takes place at spikes placed in between the starting materials. © University of Augsburg/EP VI

    Physicists from Augsburg University together with colleagues from Oxford report on a novel method for the growth of lithium-based transition metal oxides. Augsburg/PhG/KPP -The synthesis of ceramic crystals often requires very complicated methods. Starting materials in form of powders have to be mixed, pressed and pre-reacted in order to allow for single crystal growth from the melt at elevated temperatures. Or samples are grown from solution or chemical vapor transport in complex processes. However, so far none of the established methods yields single crystals of lithium iridate - despite the great interest in this material that was initiated by the prediction of highly unusual magnetic properties.

  • Slow, But Efficient

    The electron kinetic energy spectrum from Ar clusters interacting with intense laser pulses is dominated by a low-energy structure (orange area). Bernd Schütte

    For the past 30 years intense laser cluster interactions have been seen primarily as a way to generate energetic ions and electrons. In surprising contrast with the hitherto prevailing paradigm, a team of researchers has now found that copious amounts of relatively slow electrons are also produced in intense laser cluster interactions.