“COAXshield” – novel local shielding nozzle system for laser metal deposition applications with sensitive materials. © Fraunhofer IWS Dresden

"COAXshield" and "LIsec": Fraunhofer IWS presents shielding gas nozzle and light scanner for laser powder build-up welding at "formnext" trade fair. Additive manufacturing systems can generate highly complex components, which could not be produced with conventional machine tools or only with great effort. Nevertheless, such industrial 3D printers are far from being standard equipment in factories. This is not just due to the purchase costs, but also to many other challenges.

An x–y view of a section 2.5 mm from the top surface of a Thy1-eGFP PEGASOS-cleared brain. Close-up of the box with a rendered neuron. Insets provide magnified views of synaptic spines. Reto Fiolka

Our brain consists of countless nerve cells that transmit signals from one cell to the next. The connections between these cells, the synapses, provide a key to understanding how our memory works. An American research team in collaboration with Rainer Heintzmann from the Leibniz Institute of Photonic Technology (Leibniz IPHT) and the Friedrich Schiller University Jena has now succeeded in identifying these switching points in millimeter-sized tissue with a light microscope on the basis of their structure. The scientists published their results on 31 October 2019 in Nature Methods.

Topological quantum states in graphene induced by light. Benedikt Schulte, MPSD

Discovering ways to control the topological aspects of quantum materials is an important research frontier because it can lead to desirable electrical and spin transport properties for future device technologies. Now MPSD scientists have discovered a pioneering laser-driven approach to generate a topological state in graphene. Their work has just been published in Nature Physics.
In topological materials, electrons experience a twisted world. Instead of simply moving straight ahead when feeling a force, they may be pushed sideways. In such a material current actually flows orthogonally to an applied voltage.

For the first time, scientists at Fraunhofer IWS printed 3D high-entropy demonstrator structures made of the Cantor alloy "CrMnFeCoNi" using the Fused Filament Fabrication (FFF) process. © Fraunhofer IWS Dresden

Symposium in Dresden focuses on a new class of materials.
A new class of materials promises many innovations in aviation, turbine construction and other branches of industry: High entropy alloys (HEA) are metals in which five or more elements are atomically bonded in similar proportions. Properly designed, they are harder, more heat-resistant and lighter than steel, aluminum and other classic materials. For about 15 years, engineers around the world have been trying to make these innovative materials ready for series production. But high-entropy alloys are still too expensive and difficult to process.

The energy behavior of the giant atom shows a memory. Lingzhen Guo/Max Planck Institute for the Science of Light

An international research group has observed new quantum properties on an artificial giant atom and has now published its results in the high-ranking journal Nature Physics. The quantum system under investigation apparently has a memory - a new finding that could be used to build a quantum computer. The research group, consisting of German, Swedish and Indian scientists, has investigated an artificial quantum system and found new properties. The experiments were done at Chalmers University of technology (Sweden) and the theory was done by Dr. Lingzhen Guo at Max Planck Institute for the Science of Light (MPL) in Erlangen. The measured effect has never been observed on a single quantum system.

Quantum circuit, developed at the Walther-Meissner-Institut (WMI), which can be used to produce restricted microwave states. Image: Andreas Battenberg / TUM

An international team headed by physicists from the Technical University of Munich (TUM) has, for the first time ever, experimentally implemented secure quantum communication in the microwave band in a local quantum network. The new architecture represents a crucial step on the road to distributed quantum computing. As of yet, there are no universal quantum computers in the world. But for the first time, an international team led by TUM physicists Rudolf Gross, Frank Deppe and Kirill Fedorov has successfully implemented secure quantum communication in a local network – via a 35-centimeter superconducting cable.

As the loading with curcumin (yellow) increases, the dissolution rate of the containers made of polymeric micelles (blue) decreases. (Picture: Ann-Christin Pöppler)

Nanocontainer for drugs can have their pitfalls: If they are too heavily loaded, they will only dissolve poorly. Why this happens is now reported by a Würzburg research group in "Angewandte Chemie". Nanocapsules and other containers can transport drugs through a patient's body directly to the origin of the disease and release them there in a controlled manner. Such sophisticated systems are occasionally used in cancer therapy. Because they work very specifically, they have fewer side effects than drugs that are distributed throughout the entire organism.

A quantum well narrows in the middle to a quantum point contact. Würzburg physicists have produced this device using new methods of nanostructuring. Picture: Christoph Fleckenstein / University of Wuerzburg

Physicists at the University of Würzburg have made a ground-breaking discovery: They have realized a fundamental nanoelectronic device based on the topological insulator HgTe previously discovered in Würzburg. Topological insulators are materials with astonishing properties: Electric current flows only along their surfaces or edges, whereas the interior of the material behaves as an insulator. In 2007, Professor Laurens Molenkamp at Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany, was the first who experimentally demonstrated the existence of such topological states. His team achieved this seminal work with quantum wells based on mercury and tellurium (HgTe). Since then, these novel materials have been the hope for a fundamentally new generation of components that, for example, promise innovations for information technology.

Small fraction of dendrites (gray) and synapses (orange) in a piece of mouse cortex, reconstructed from 3D electron microscopy data. Motta, Wissler (c) MPI for Brain Research

Mammalian brains, with their unmatched number of nerve cells and density of communication, are the most complex networks known. While methods to analyze neuronal networks sparsely have been available for decades, the dense mapping of neuronal circuits is a major scientific challenge. Researchers from the MPI for Brain Research have now succeeded in the dense connectomic mapping of brain tissue from the cerebral cortex, and quantify the possible imprint of learning in the circuit.

Energy transport in biomimetic nanotubes (left) and a three-dimensional spectrum (right). Bjoern Kriete (l.) / Stefan Mueller (r.)

It is crucial for photovoltaics and other technical applications, how efficiently energy spreads in a small volume. With new methods, the path of energy in the nanometer range can now be followed precisely. Plants and bacteria lead the way: They can capture the energy of sunlight with light-harvesting antennas and transfer it to a reaction centre. Transporting energy efficiently and in a targeted fashion in a minimum of space – this is also of interest to mankind. If scientists were to master it perfectly, they could significantly improve photovoltaics and optoelectronics.

Light pulses can form pairs in ultra-short pulse lasers. The pulse intervals (red) can be precisely adjusted by making certain changes to pump beam (green). Image: UBT.

Ultrashort laser pulses have enabled scientists and physicians to carry out high-precision material analyses and medical procedures. Physicists from the University of Bayreuth and the University of Göttingen have now discovered a new method for adjusting the extremely short time intervals between laser flashes with exceptional speed and precision. The intervals can be increased or decreased as needed, all at the push of a button. Potential applications range from laser spectroscopy to microscopy and materials processing. The researchers have now presented their latest findings in the journal Nature Photonics.

Left: Schematic illustration for the SMAIS method for 2D polymer synthesis, Right: High-resolution transmission electron microscopic image for 2D polyimide Left: by Marc Hermann, TRICKLABOR), Right: by Dr. Haoyuan Qi, Uni Ulm

Scientists at the Center for Advancing Electronics Dresden (cfaed) at TU Dresden have succeeded in synthesizing sheet-like 2D polymers by a bottom-up process for the first time. A novel synthetic reaction route was developed for this purpose. The 2D polymers consist of only a few single atomic layers and, due to their very special properties, are a promising material for use in electronic components and systems of a new generation. The research result is a collaborative work of several groups at TU Dresden and Ulm University and was published this week in two related articles in the scientific journals "Nature Chemistry" and "Nature Communications".

At formnext, Fraunhofer ILT will be showing a new processing head that enables wire LMD in hybrid processes as part of the BMBF's ProLMD project. © Fraunhofer ILT, Aachen, Germany.

Within a BMBF-funded project, the Fraunhofer Institute for Laser Technology ILT is tackling the issue of 3D printing large components economically by using a new process called Hybrid AM that combines conventional manufacturing with additive processes. An important step forward in this process development is a new wire LMD head and its modular components which the Aachen-based experts will be presenting for the first time at formnext from November 19 to 22, 2019 in Frankfurt am Main.

Charges in organic semiconductors can be trapped by either oxygen or water molecules. © D. Andrienko, MPI-P

For applications such as light-emitting diodes or solar cells, organic materials are nowadays in the focus of research. These organic molecules could be a promising alternative to currently used semiconductors such as silicon or germanium and are used in OLED displays. A major problem is that in many organic semiconductors the flow of electricity is hampered by microscopic defects. Scientists around Dr. Gert-Jan Wetzelaer and Dr. Denis Andrienko of the Max-Planck-Institute for Polymer Research have now investigated how organic semiconductors can be designed such that the electric conduction is not influenced by these defects.

A monolayer of organic molecules is placed in the focused light field and replies to this illumination by fluorescence, embedding all information about the invisible properties. Pascal Runde

Physicists and chemists at the University of Münster (Germany) have jointly succeeded in developing a so-called nano-tomographic technique which is able to detect the typically invisible properties of nano-structured fields in the focus of a lens. Such a method may help to establish nano-structured light landscapes as a tool for material machining, optical tweezers, or high-resolution imaging. The study was published in "Nature Communications".

The combination of magnetism and topology leads to new sciences and applications in thermoelectric, spintronic, photovoltaic, quantum computing, and other quantum technologies. © MPI CPfS

Imagine a world in which electricity could flow through the grid without any losses or where all the data in the world could be stored in the cloud without the need for power stations. This seems unimaginable but a path towards such a dream has opened with the discovery of a new family of materials with magical properties. These materials – magnetic Weyl semi-metals – are innately quantum but bridge the two worlds of topology and spintronics. Topological materials exhibit strange properties including super-fast electrons that travel without any energy loss.