Spin fluctuation induced Weyl semimetal state in the paramagnetic phase of EuCd2As2
Weyl fermions as emergent quasiparticles can arise in Weyl semimetals (WSMs) in which the energy bands are nondegenerate, resulting from inversion or time-reversal symmetry breaking. Nevertheless, experimental evidence for magnetically induced WSMs is scarce. Here, using photoemission spectroscopy, we observe that the degeneracy of Bloch bands is already lifted in the paramagnetic phase of EuCd2As2. We attribute this effect to the itinerant electrons experiencing quasi-static and quasi–long-range ferromagnetic fluctuations.
Molecular energy machine as a movie star
Using the Swiss Light Source SLS, PSI researchers have recorded a molecular energy machine in action and thus revealed how energy production at cell membranes works. For this purpose, they developed a new investigative method that could make the analysis of cellular processes significantly more effective than before.
PSI School for Master Degree Students - Introducing Photons, Neutrons and Muons for Condensed Matter Physics and Materials Science
From 17 – 21 June 2019 the Neutron and Muon Division (NUM) and the Photon Science Division (PSD) of PSI hosted 18 Master Degree students of physics, chemistry, materials and interdisciplinary science, as well as nuclear engineering to provide an introduction to the characterization of materials with large scale facilities like SINQ, SμS, SLS and SwissFEL. The course taught a basic understanding of how photons, neutrons and muons interact with matter, and how this knowledge can be used to solve specific problems in materials research.
Details of the program can be found at http://indico.psi.ch/event/PSImasterschool
New material also reveals new quasiparticles
Researchers at PSI have investigated a novel crystalline material at the Swiss Light Source SLS that exhibits electronic properties never seen before. Among other things, they were able to detect a new type of quasiparticle: so-called Rarita-Schwinger fermions.
HERCULES school 2019 at SLS
In the week of April 1-5 PSI welcomes 20 PhD students and postdocs taking part in the European HERCULES 2019 school on Neutron and Synchrotron Radiation. They will attend lectures and perform two days of practical courses at several beam lines of the Swiss Light Source.
Additive Manufacturing of High Entropy Alloys
Additive manufacturing of high-entropy alloys combines the mechanical properties of this novel family of alloys with the geometrical freedom and complexity required by modern designs. An approach to additive manufacturing of high-entropy alloys has been developed based on 3D extrusion of inks containing a blend of oxide nanopowders (Co3O4 + Cr2O3 + Fe2O3 + NiO), followed by co-reduction to metals, inter-diffusion and sintering to near-full density CoCrFeNi in H2. A complex phase evolution path is observed by in-situ X-ray diffraction in extruded filaments: the oxide phases undergo reduction and the resulting metals inter-diffuse, ultimately forming the desired fcc-CoCrFeNi alloy (see figure). Linked to this phase evolution is a complex micro-structural one, from loosely packed oxide particles to fully-annealed, metallic CoCrFeNi with 99.6 ± 0.1% relative density. CoCrFeNi micro-lattices are created with strut diameters as low as 100 μm and excellent mechanical properties at ambient and cryogenic temperatures.
Insights into a well-known disease in ageing populations: Abdominal and popliteal aneurysm
Abdominal aortic aneurysm, an enlargement of the abdominal aorta, may lead to rupture and thus acute health issues and death. Scanning X-ray imaging enabled new insights in the nano-structure of calcifications associated with abdonimal and popliteal aneurysm and allowed mapping the distribution of nano- and micro-calcifications as well as of collagen, elastin and myofilament as building blocks of connective tissue across samples from human donors.
Virtual lens improves X-ray microscopy
A method developed by PSI researchers makes X-ray images of materials even better. The researchers took a number of individual images while moving an optical lens. From these, with the help of computer algorithms, they generated one overall image.
EU grants 14 million to Swiss Researchers
A team with three researchers from the ETH Domain has been awarded a prestigious EU grant. Today, they received the contract signed by the EU confirming the extraordinary 14 million euros funding. With it, they will investigate quantum effects which could become the backbone of future electronics.