Shifting away from nuclear energy, expanding solar and wind power, generating energy from biomass, reducing energy consumption. Switzerland is committed to becoming climate-neutral by 2050. An ambitious goal, which has become more urgent than ever due to the increasingly challenging geopolitical situation. How can a sustainable and resilient energy supply for Switzerland be established over the coming years? What's the optimal way to use renewable energy sources? What new technologies are especially promising? At PSI, researchers are seeking answers to these crucial questions.
In-situ Studies of the Reactivity of Model Catalysts: Surface Chemistry from flat surfaces to nanoparticles
On 7th February Dr. Christian Papp from University Erlangen (Germany) is visiting the SIM beamline and will give a Photon Science Seminar talk with the title: "In-situ Studies of the Reactivity of Model Catalysts: Surface Chemistry from flat surfaces to nanoparticles"
Historical copper, trapped in ice
Until now, the onset of copper production in South America was still unclear. Hardly any written records or artefacts from the early high cultures in Peru, Chile, and Bolivia have been preserved. Now, however, researchers of the Paul Scherrer Institute PSI in Villigen (Switzerland) have tracked down the evidence. Through analysis of ice from the Illimani glacier in the Bolivian Andes, they found out that copper was being mined and smelted in South America since around 700 BC.
Thomas Lippert new Editor-in-Chief of Applied Physics A
Prof. Dr. Thomas Lippert has been appointed as new "Editor in Chief" of the journal Applied Physics A(link is external). He succeeds Michael Stuke who served Applied Physics A more than 20 years as an Editor in Chief.
In cold water
Martin Ostermaier wanted to break out of the comfort zone of science. Now, instead of pipettes, the biochemist is dealing with investors and patent law.
A Miniaturized Biaxial Deformation Rig for in situ Mechanical Testing
Researchers at PSI have developed a new unique miniaturized biaxial deformation rig, which allows to apply in-plane biaxial stress states with arbitrary stress ratios and to perform strain path changes on thin-sheet metals. The device is optimized for in situ usage inside a scanning electron microscope and at synchrotron beam lines.
Higher methane yield from bio-waste
Within Switzerland’s bio-waste a huge amount of precious energy is hidden. That’s because valuable methane, the main constituent of natural gas, can be obtained from it. With a technology developed at PSI, the yield of methane from bio-waste could be increased considerably in the future. A long-term test conducted in cooperation with Energie 360° at the Werdhölzli fermentation and wastewater treatment plant is expected to advance this technology further along its path to industrial use.
Full Elasticity Tensor from Thermal Diffuse Scattering
We present a method for the precise determination of the full elasticity tensor from a single crystal diffraction experiment using monochromatic X-rays. For the two benchmark systems calcite and magnesium oxide, we show that the measurement of thermal diffuse scattering in the proximity of Bragg reflections provides accurate values of the complete set of elastic constants.
Added value for cancer patients
At the Paul Scherrer Institute PSI, cancer patients receive a treatment that is unique in Switzerland: proton therapy. This state-of-the-art form of radiation therapy against cancer has major advantages, compared to conventional irradiation, in terms of effectiveness and side-effects. The PSI has its own Center for Proton Therapy dedicated to this special treatment. Its pioneering work has not only helped several thousand patients, but also has fundamentally changed proton therapy worldwide.
Annual Retreat of the Microscopy & Magnetism Group
The Magnetism and Microscopy group has met for its annual retreat meeting in Lungern 11- 15.1.2017 (in the central mountain region of Switzerland) for extensive discussions on its science program. As for other years, after some general introductory lecture into the techniques used, current and future projects have been presented by the PhD students, postdocs, and scientists as well as from guests who collaborate with the group. Discussion went into the time where dinner has been prepared together, followed by some leisure activities on Saturday.
Suppression of magnetic excitations near the surface of the topological Kondo insulator SmB6
We present a detailed investigation of the temperature and depth dependence of the magnetic properties of the three-dimensional topological Kondo insulator SmB6, in particular, near its surface. We find that local magnetic field fluctuations detected in the bulk are suppressed rapidly with decreasing depths, disappearing almost completely at the surface.
Structure and Interaction in the pH-Dependent Phase Behavior of Nanoparticle−Protein Systems
The pH-dependent structure and interaction of anionic silica nanoparticles (diameter 18 nm) with two globular model proteins, lysozyme and bovine serum albumin (BSA), have been studied. Cationic lysozyme adsorbs strongly on the nanoparticles, and the adsorption follows exponential growth as a function of lysozyme concentration, where the saturation value increases as pH approaches the isoelectric point (IEP) of lysozyme.
Nanotechnology enables new insights into chemical reactions
Eighty percent of all products of the chemical industry are manufactured with catalytic processes. Catalysis is also indispensable in energy conversion and treatment of exhaust gases. Industry is always testing new substances and arrangements that could lead to new and better catalytic processes. Researchers of the Paul Scherrer Institute PSI in Villigen and ETH Zurich have now developed a method for improving the precision of such experiments, which may speed up the search for optimal solutions.
New sewage cleaning system and tank farm
PSI Hotlab is collecting and radiologically cleaning the entire radioactive waste water from the PSI East side. In the years 2014-2016 a major refurbishment took place, where the old tank farm was decommissioned, and new stainless-steel tanks were installed together with new, modern ultrafiltration systems during normal operation of the lab.
A three-dimensional movie of structural changes in bacteriorhodopsin
Snapshots of bacteriorhodopsinBacteriorhodopsin is a membrane protein that harvests the energy content from light to transport protons out of the cell against a transmembrane potential. Nango et al. used timeresolved serial femtosecond crystallography at an x-ray free electron laser to provide 13 structural snapshots of the conformational changes that occur in the nanoseconds to milliseconds after photoactivation. These changes begin at the active site, propagate toward the extracellular side of the protein, and mediate internal protonation exchanges that achieve proton transport.
Can a metal nanotip array device be a low-emittance and coherent cathode?
A nanofabricated low emittance field emitter array cathode was demonstrated for the first time, and successfully applied to observe the low-energy electron diffraction from suspended monolayer graphene. The work has an impact on the future development of compact X-ray free electron lasers, THz/RF vacuum electronic sources, and ultrafast electron imaging and diffraction experiments.
The Dynamics of Nuclear Reactors
Nuclear reactor dynamics deals with the transient behaviour of nuclear reactors which mostly refers to time changes of the imbalance between heat production and removal. Since the prediction of the dynamic behaviour is crucial for the safety of a reactor, computational models and methodologies have been developed in the framework of the STARS project, at the Laboratory for Reactor Physics and Thermal-Hydraulics (LRT), with the main goal to simulate the complex behaviours of reactors under various conditions with a high level of fidelity.
Towards energy-saving data storage
A new material could become the basis for future data storage devices, since it may enable significant reductions in energy demands in comparison to present-day hard drives. It is a material from the class of so-called magnetoelectric multiferroics, exhibiting the necessary magnetic properties even at room temperature.
Tuning magnetic spirals beyond room temperature with chemical disorder
Frustrated magnets with spiral magnetic orders are of high current interest due to their potential for spintronics and low-power magnetoelectric devices. However, their low magnetic order temperatures (typically <100K) greatly restrict their fields of application. Researchers of PSI have demonstrated that the stability domain of the spiral phase in the perovskite YBaCuFeO5 can be enlarged by more than 150K through a controlled manipulation of the Fe/Cu chemical disorder.
The open-air researchers
Atmospheric scientist Julia Schmale is starting out on a three-month research cruise around the antartic. There she will be searching for the cleanest air still to be found on our planet.
In the focus of the protons
At the PSI, researchers work with radioactivity every day in order to develop advanced treatment methods for patients. Naturally, they take special safety precautions working with a material that decays. It's a race against time. To make sure everything functions smoothly, a dedicated work group takes care of the infrastructure.
Back to life
Doctors had discovered, behind Gabi Meier’s right eye, a tumour that surrounded the optic nerve. Only at the PSI was there still one possibility to treat the tumour in such a way as to preserve neighbouring structures and the eye. A few months after the proton treatment was over, I realised that I could see more and more, she said in an interview. “Just dimly, it’s true, but I could see! That was sensational!”
SwissFEL inauguration
Today, on 5 December 2016, the Paul Scherrer Institute PSI held an inauguration ceremony for its new large-scale research facility SwissFEL, with Johann N. Schneider-Ammann, President of the Swiss Confederation, in attendance.
SwissFEL First Lasing
On Friday December 2nd at 1am SwissFEL observed for the first time FEL lasing in the undulator line. The lasing was achieved with a commission beam of low intensity, repetition rate and energy, i.e. 100pC/bunch, 1Hz and 377MeV. The 12 undulators were set to a K value of 1.2. The resulting wavelength computed from beam energy and undulator K value is 24nm. The FEL signal was observed with a Si-diode detector. The spontaneous radiation signal with uncompressed electron beam increased by a large factor when the beam was compressed from 10ps to about 1ps at constant charge and electron beam energy. By opening the undulator gaps a first FEL gain curve was measured.
Extreme optical and electronic nonlinearities in GaP induced by an ultrastrong Terahertz field
Researchers from the SwissFEL laser group have succeeded in using intense Terahertz radiation to dramatically change the optical properties of a semiconductor on a sub-cycle timescale. In their experiment the material Gallium Phosphide (GaP) was illuminated by an extremely strong THz electric field with up to 50 MV/cm in strength.
Magnetic Excitations and Electronic Interactions in Sr2CuTeO6: A Spin-1/2 Square Lattice Heisenberg Antiferromagnet
Sr2CuTeO6 presents an opportunity for exploring low-dimensional magnetism on a square lattice of S=1/2 Cu2+ ions. We employ ab initio multireference configuration interaction calculations to unravel the Cu2+ electronic structure and to evaluate exchange interactions in Sr2CuTeO6.
Pressure and temperature dependence of the laser-induced plasma plume dynamics
The influence of different background gases and substrate heating on the plasma plume dynamics from silver ablation is investigated by species selected time and space resolved imaging. The results provide a time-resolved understanding on how those process parameters affect the expansion: from a free expansion in vacuum with velocities exceeding 20'000 m/s to a very slow expansion in Ar at 1 × 10−1 mbar with arrival velocities of 280 m/s.
Simulations for More Efficient Power Stations
In most cases, electricity is generated when water is heated and transformed into vapour. Vapour bubbles in the water play a decisive role in this process. Using computer simulation, researchers at the Paul Scherrer Institute have succeeded in representing the behaviour of vapour bubbles – and in making their performance more calculable.
20 years of high-precision combat against cancer
On 25.11.1996, at the Paul Scherrer Institute PSI, the world’s first cancer patient was treated with a new irradiation method: the so-called spot-scanning technique for proton beams. What’s special about it: The beam has its effect only at the depth where the tumour is located; healthy tissue above and below it is preserved. The method, developed by PSI researchers, was a breakthrough at the time and quickly became a successful product.
Electromagnon dispersion probed by inelastic X-ray scattering in LiCrO2
Lattice vibrations (phonons) in crystals are typically weakly interacting with the electronic and magnetic degrees of freedom, such as charge and spin fluctuations. Researchers of PSI together with collaborators from EPF Lausanne, Japan and USA discovered an unexpectedly strong coupling between lattice vibrations and spin fluctuations in the quantum magnet LiCrO2. The observed magnetoelastic waves or electromagnons carry both electric and magnetic dipole moment.
Detecting and utilizing minority phases in heterogeneous catalysis
Highly active phases in carbon monoxide oxidation are known, however they are transient in nature. Here, we determined for the first time the structure of such a highly active phase on platinum nanoparticles in an actual reactor.