Scientific Highlights from PSI's research divisions
Research with Neutrons and Muons (NUM)
Observation of plaquette fluctuations in the spin-1/2 honeycomb lattice
Quantum spin liquids are materials that feature quantum entangled spin correlations and avoid magnetic long-range order at T =0 K. Particularly interesting are two-dimensional honeycomb spin lattices where a plethora of exotic quantum spin liquids have been predicted. Here, we experimentally study an effective S = 1/2 Heisenberg honeycomb lattice with competing nearest and next-nearest-neighbour interactions.
Revealing Creep Motion of a Skyrmion Lattice at Ultra-Low Current Densities
Magnetic skyrmions are well-suited for encoding information because they are nano-sized, topologically stable, and only require ultra-low critical current densities jc to depin from the underlying atomic lattice. Above jc, skyrmions exhibit well-controlled motion, making them prime candidates for race-track memories. In thin films thermally-activated creep motion of isolated skyrmions was observed below jc as predicted by theory.
Photon Science Division (PSD)
Milestone for the second beamline of SwissFEL
At the X-ray free-electron laser SwissFEL of the Paul Scherrer Institute PSI, the second beamline is currently being put into operation. With Athos, researchers want to understand how catalysts work or how biomolecules cause hereditary diseases.
Magnetic vortices come full circle
The first experimental observation of three-dimensional magnetic ‘vortex rings’ provides fundamental insight into intricate nanoscale structures inside bulk magnets, and offers fresh perspectives for magnetic devices.
Biology and Chemistry (BIO)
Bringing information into the cell
Researchers at the Paul Scherrer Institute PSI have elucidated an important part of a siganalling pathway that transmits information through the cell membrane into the interior of a cell. This exists in all mammals and plays an important role, among other things, in the regulation of the heartbeat. The new findings could lead to new therapies.
A biotechnological revolution
Gebhard Schertler is head of the research division Biology and Chemistry at the Paul Scherrer Institute PSI and professor for Structural Biology at ETH Zurich. In this interview he talks about biological research at PSI and the future of drug development.
General Energy (ENE)
Aerosol distribution in rooms and the importance of proper ventilation
Urs Baltensperger explains the background why it is absolutely necessary to wear masks in order to reduce the risk of beeing infected with Covid-19.
In the following you find the presentation and summary
Einfache Experimente zeigen: so gut schützen uns Masken und andere Materialien
Spätestens seit Corona ist der Maskengebrauch auch in der Schweiz im Alltag präsent. Doch wie gut können wir uns und andere mit verschieden Materialien vor kleineren und grösseren Partikeln schützen? Das alljährlich durchgeführte PSI Feriencamp bietet Kindern einen spannenden Einblick in die faszinierende Welt der Forschung. In diesem Jahr gingen Kinder an einer Projektstation genau dieser Frage nach. Dabei untersuchten sie, wie gut verschiedene Materialien die im Labor generierten Partikel zurückhalten. Es wurden Textilmasken (im Handel erhältlich, wiederverwendbar, nicht FFP2-zertifiziert), Chirurgenmasken (Einwegmasken, FFP2-zertifiziert), Teefilter, Kaffeefilter, Papiertaschentuch und WC-Papier getestet, und es wurde klar, Maske ist nicht gleich Maske.
Nuclear Energy and Safety Research (NES)
New element and speciation specific analytical options at AHL
The Hot Laboratory division (AHL) within PSI’s Nuclear Energy and Safety (NES) division continually upgrades and advances its analytical infrastructure to provide cutting-edge scientific service to PSI’s researchers and industrial customers. A new, fully automatable and highly flexible Ion Chromatograph (IC) furthers AHL’s efforts in sample miniaturization and extends the spectrum of destructive analytical capabilities to element and speciation specific analyses. With the new IC and its modern ICP-MS (Inductively Coupled Plasma Mass Spectrometry) facilities, AHL offers innovative scientific options for nuclear and general research. Moreover, speciation analyses by IC-ICP-MS for polyvalent inorganic water pollutants such as Cr or As and the acquisition of a new ICP-OES system (Inductively Coupled Plasma Optical Emission Spectrometry) enable future autonomy in wastewater management.
Deep geological disposal of radioactive waste in clay rocks
Geological waste disposal, cement clay interaction
• A considerable reduction of HTO and 36Cl− was observed after 6 years interaction.
• The chloride flux showed a much stronger reduction compared to HTO.
• For HTO the relation between the De and the porosity in the clay part can be described using Archie's law.
• No complete clogging of the porosity was observed after 6 years interaction.
GFA
Demonstration of Large Bandwidth Hard X-Ray Free-Electron Laser Pulses at SwissFEL
We have produced hard x-ray free-electron laser (FEL) radiation with unprecedented large bandwidth tunable up to 2%. The experiments have been carried out at SwissFEL, the x-ray FEL facility at the Paul Scherrer Institute in Switzerland. The bandwidth is enhanced by maximizing the energy chirp of the electron beam, which is accomplished by optimizing the compression setup. We demonstrate continuous tunability of the bandwidth with a simple method only requiring a quadrupole magnet. The generation of such broadband FEL pulses will improve the efficiency of many techniques such as x-ray crystallography and spectroscopy, opening the door to significant progress in photon science. It has already been demonstrated that the broadband pulses of SwissFEL are beneficial to enhance the performance of crystallography, and further SwissFEL users plan to exploit this large bandwidth radiation to improve the efficiency of their measurement techniques.
Generation and measurement of ultralow-emittance electron beams at SwissFEL
The emittance is a fundamental parameter of particle distributions accounting for the average spread of the particles’ positions and momenta. We have generated and characterized intense ultralow-emittance electron beams, setting new standards for electron linear accelerators. The measurements have been carried out at the SwissFEL accelerator of PSI. SwissFEL is one of the few X-ray free-electron lasers (FELs) worldwide, which are cutting-edge research instruments to investigate matter with resolutions at the level of atomic processes.