Matter and Material

When bridges, dam walls and other structures made of concrete are streaked with dark cracks after a few decades, the culprit is the so-called the concrete disease. Researchers from the Paul Scherrer Institute PSI and Empa have now solved the structure of the material produced in these cracks at atomic level - and have thereby discovered a previously unknown crystalline arrangement of the atoms.

At first glance, the Swiss Light Source SLS stands out as a striking building. The inside reveals a setting of cutting-edge research. A journey through a world where electrons race a slalom course and X-rays help decode proteins.

Researchers from the Paul Scherrer Institute PSI have succeeded in using commercially available camera technology to visualise terahertz light. In doing so, they are enabling a low-cost alternative to the procedure available to date, whilst simultaneously increasing the comparative image resolution by a factor of 25. The special properties of terahertz light make it potentially advantageous for many applications. At PSI, it will be used for the experiments on the X-ray free-electron laser SwissFEL.

Researchers at the Paul Scherrer Institute (PSI) created a synthetic material out of 1 billion tiny magnets. Astonishingly, it now appears that the magnetic properties of this so-called metamaterial change with the temperature, so that it can take on different states; just like water has a gaseous, liquid and a solid state.

For increasingly compact storage media, magnetic areas – the memory bits – also need to become smaller and smaller. But just how small can a magnet be? Frithjof Nolting and his colleagues at the Paul Scherrer Institute investigate the surprising phenomena in the field of nanomagnetism.

Researchers from the Paul Scherrer Institute have managed to focus the light pulse terahertz laser at the limit of what is permitted by the classical laws of physics. This opens up new possibilities for studying the properties of materials.

For the first time, an international research team has demonstrated how to generate magnetism in metals that aren’t naturally magnetic, such as copper. The discovery could help develop novel magnets for a wide range of technical applications. Crucial measurements to understand this phenomenon were carried out at PSI à the only place where magnetic processes inside materials can be studied in sufficient detail.

Researchers from the Paul Scherrer Institute have succeeded in creating regular patterns in a semiconductor material that are sixteen times smaller than in today’s computer chips. As a result, they have taken an important step closer towards even smaller computer components. Industry envisages structures on this scale as the standard for the year 2028.

Scientists at the Paul Scherrer Institute and ETH Zurich have created 3D images of tiny objects showing details down to 25 nanometres. In addition to the shape, the scientists determined how particular chemical elements were distributed in their sample and whether these elements were in a chemical compound or in their pure state.

Germanium-Zinn-Halbleiterlaser lässt sich direkt auf Siliziumchips aufbringenWinzige Laser, die in Computerchips aus Silizium eingebaut werden, sollen in Zukunft die Kommunikation innerhalb der Chips und zwischen verschiedenen Bauteilen eines Computers beschleunigen. Lange suchten Experten nach einem dafür geeigneten Lasermaterial, das sich mit dem Fertigungsprozess von Siliziumchips vereinbaren lässt. Wissenschaftler des Forschungszentrums Jülich und des Paul Scherrer Instituts PSI haben hier nun einen wichtigen Fortschritt erzielt.This news release is only available in German.

Researchers at the Paul Scherrer Institute (PSI) have succeeded in switching tiny, magnetic structures using laser light and tracking the change over time. In the process, a nanometre-sized area bizarrely reminiscent of the Batman logo appeared. The research results could render data storage on hard drives faster, more compact and more efficient.

New effect might be important for emergence of High-Temperature SuperconductivityAn international team of researchers has observed a new, unexpected kind of behaviour in copper-based high-temperature superconductors. Explaining the new phenomenon à an unexpected form of collective movement of the electrical charges in the material à poses a major challenge for the researchers. A success in explaining the phenomenon might be an important step toward understanding high-temperature superconductivity in general. The crucial experiments were conducted at the Paul Scherrer Institute.

The need for ever faster and more efficient electronic devices is growing rapidly, and thus the demand for new materials with new properties. Oxides, especially ones based on strontium titanate (SrTiO₃), play an important role here. A collaborative project headed by scientists from the PSI has now revealed properties of strontium titanate that make it an important base material for applications in spintronics.

PSI researchers garner experience for SwissFEL experimentsAided by short laser flashes, researchers at the Paul Scherrer Institute have managed to temporarily change a material’s properties to such a degree that they have à to a certain extent àcreated a new material. This was done using the x-ray laser LCLS in California. Once the PSI x-ray laser SwissFEL is up and running, experiments of this kind will also be possible at PSI.

Researchers at the PSI, the EPFL and the Chinese Academy of Science, have proven that the material SmB₆ shows all the properties of a so called topological insulator à a material with electric currents flowing along its surface with all of them being polarized. Here, the property is very robust, i.e. the only current that can flow is spin polarized and is not easily destroyed by small irregularities in the structure or composition of the material. Spin polarized currents are necessary for spintronics, electronics using the electrons’ spin.

Processes in stars recreated with isotopes from PSIIsotopes that otherwise only naturally exist in exploding stars à supernovae à are formed at the Paul Scherrer Institute’s research facilities. This enables processes that take place inside the stars to be recreated in the lab. For instance, an international team of researchers used the titanium isotope Ti-44 to study one such process at CERN in Geneva. In doing so, it became evident that it is less effective than was previously believed and the previous theoretical calculations of processes in stars need to be corrected.

Researchers from ETH Zurich and the Paul Scherrer Institute PSI demonstrate how the magnetic structure can be altered quickly in novel materials. The effect could be used in efficient hard drives of the future.

Materials research, particle physics, molecular biology, archaeology à for the last forty years, the Paul Scherrer Institute’s large-scale proton accelerator has made top-flight research possible in a number of different fields.

Superconductivity and magnetic fields are normally seen as rivals à very strong magnetic fields normally destroy the superconducting state. Physicists at the Paul Scherrer Institute have now demonstrated that a novel superconducting state is only created in the material CeCoIn₅ when there are strong external magnetic fields. This state can then be manipulated by modifying the field direction. The material is already superconducting in weaker fields, too. In strong fields, however, an additional second superconducting state is created which means that there are two different superconducting states at the same time in the same material.

Above the transition temperature, some electrons in the superconducting material La_1.77Sr_0.23CuO₄ behave as if they were in a conventional metal, others as in an unconventional one à depending on the direction of their motion. This is the result of experiments performed at the SLS. The discovery of this anisotropy makes an important contribution towards understanding high-temperature superconductors. The effect will also have to be taken into account in future experiments and theories of high-temperature superconductors.