Research on Covid-19

At PSI, several projects are dedicated to important research questions concerning the Sars-CoV-2 coronavirus and the resulting diseases. We provide information on activities and projects, for example on investigations of lung tissue, on the production of proteins and antibodies or on ideas for new research on Covid-19.

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2021_Kiwi

Bedürfnisorientierte Spielangebote in der Kita Kiwi

Was heisst bedürfnisorientierte Spielangebote anbieten und was löst es aus?

2021_PM_Gold_wert

Gold wert - "Was wir machen, machen wir richtig"

Erfahrungen aus der Teilprüfungsvorbereitungen und was haben wir daraus gelernt?

Grinenko_nc

Unsplit superconducting and time reversal symmetry breaking transitions in Sr2RuO4 under hydrostatic pressure and disorder

There is considerable evidence that the superconducting state of Sr2RuO4 breaks time reversal symmetry. In the experiments showing time reversal symmetry breaking, its onset temperature, TTRSB, is generally found to match the critical temperature, Tc, within resolution. In combination with evidence for even parity, this result has led to consideration of a dxz ± idyz order parameter.

 

PR

LRC and BluAct explore innovative filter material

Fission products from the PSI-SINQ gas-jet facility, as operated by LRC, were used to reveal the separation of relevant radionuclides from radioactively contaminated water. The tests were conducted using a novel innovative filter material made of a blend of milk whey and active charcoal on cellulose. This material has been developed by the ETHZ spin-off BluAct Technologies GmbH.

The importance of this project was recently highlithed in ETSON/news

PSI e-Learning Produktionen erneut ausgezeichnet

Zum dritten Mal in Folge wurden zwei unserer hauseigenen e-Learning Produktionen mit einem Siegel des renommierten Comenius EduMedia Awards für exemplarische Bildungsmedien ausgezeichnet.

Klein et al

RENiO3 Single Crystals (RE = Nd, Sm, Gd, Dy, Y, Ho, Er, Lu) Grown from Molten Salts under 2000 bar of Oxygen Gas Pressure

The electronic properties of transition-metal oxides with highly correlated electrons are of central importance in modern condensed-matter physics and chemistry, both for their fundamental scientific interest and for their potential for advanced electronic applications. However, the design of materials with tailored properties has been restricted by the limited understanding of their structure–property relationships, which are particularly complex in the proximity of the regime where localized electrons become gradually mobile. RENiO3 perovskites, characterized by the presence of spontaneous metal to insulator transitions, are some of the most widely used model materials for the investigation of this region in theoretical studies. However, crucial experimental information needed to validate theoretical predictions is still lacking due to their challenging high-pressure synthesis, which has prevented to date the growth of sizable bulk single crystals with RE ≠ La, Pr, and Nd. Here we report the first successful growth of single crystals with RE = Nd, Sm, Gd, Dy, Y, Ho, Er, and Lu in sizes up to ∼75 μm, grown from molten salts in a temperature gradient under 2000 bar of oxygen gas pressure. The crystals display regular prismatic shapes with flat facets, and their crystal structures and metal–insulator and antiferromagnetic order transition temperatures are in excellent agreement with previously reported values obtained from polycrystalline samples. The availability of such crystals opens access to measurements that have hitherto been impossible to conduct. This should contribute to a better understanding of the fascinating properties of materials with highly correlated electrons and guide future efforts to engineer transition-metal oxides with tailored functional properties.

2021 Lasagne

Mein kulinarischer Alltag

Herausforderung: Gemüselasagne

Klein et al

RENiO3 Single Crystals (RE = Nd, Sm, Gd, Dy, Y, Ho, Er, Lu) Grown from Molten Salts under 2000 bar of Oxygen Gas Pressure

Schematic representation of the method used to grow RENiO3 nickelate single crystals covering the full 4f series and Y. This novel procedure, based on the use of moderate oxygen gas pressures (2000 bar), solvothermal growth in a temperature gradient, and highly reactive eutectic salt mixtures as fluxes, yields prismatic-shaped crystals with flat facets and sizes up to ∼75 μm.

 

Moeckli et al

Two scenarios for superconductivity in CeRh2As2

CeRh2As2, a nonsymmorphic heavy fermion material, was recently reported to host a remarkable temperature versus z-axis magnetic-field phase diagram with two superconducting phases. In this material, the two inequivalent Ce sites per unit cell, related by inversion symmetry, introduce a sublattice structure corresponding to an extra internal degree of freedom. In this work, we propose a classification of the possible superconducting states in CeRh2As2 from the two Ce-sites' perspective.

 

Jiang et al

Unconventional chiral charge order in kagome superconductor KV3Sb5

Intertwining quantum order and non-trivial topology is at the frontier of condensed matter physics. A charge- density-wave-like order with orbital currents has been pro- posed for achieving the quantum anomalous Hall effect in topological materials and for the hidden phase in cuprate high-temperature superconductors. However, the experimental realization of such an order is challenging. Here we use high-resolution scanning tunnelling microscopy to discover an unconventional chiral charge order in a kagome material, KV3Sb5, with both a topological band structure and a superconducting ground state.

 

Li et al

Giant phonon anomalies in the proximate Kitaev quantum spin liquid α-RuCl3

The Kitaev quantum spin liquid epitomizes an entangled topological state, for which twoflavors of fractionalized low-energy excitations are predicted: the itinerant Majorana fermion and the Z2 gauge flux. It was proposed recently that fingerprints of fractional excitations are encoded in the phonon spectra of Kitaev quantum spin liquids through a novel fractional- excitation-phonon coupling. Here, we detect anomalous phonon effects in α-RuCl3 using inelastic X-ray scattering with meV resolution.

 

acoustic levitation

On-demand sample delivery article highlighted in "Applied Physics Letters"

An article on the on-demand sample delivery and protein crystallography using acoustic levitation has been selected in an Applied Physics Letters collection of papers on technology and application of acoustic tweezers.

Encapsulation of highly dispersed palladium oxide clusters in the microporous channels and voids of the nanosized silicalite-1 crystals has been achieved by using an amine-based ligand

Stable Palladium Oxide Clusters Encapsulated in Silicalite-1 for Complete Methane Oxidation

Encapsulation of highly dispersed palladium oxide clusters in the microporous channels and voids of the nanosized silicalite-1 crystals has been achieved by using an amine-based ligand.

cryo-EM

Catching Alzheimer's Toxin

Single-particle cryo-electron microscopy of  a functional Aβ42 pore equivalent, created by fusing Aβ42 to the oligomerizing, soluble domain of the α-hemolysin  toxin, offers new insights into structure and function of proteins forming amyloid aggregates in Alzheimer’s disease.

ieee_marisa_2021

Roadmap on Magnetoelectric Materials and Devices

The possibility of tuning the magnetic properties of materials with voltage (converse magnetoelectricity) or generating electric voltage with magnetic fields (direct magnetoelectricity) has opened new avenues in a large variety of technological fields, ranging from information technologies to healthcare devices and including a great number of multifunctional integrated systems, such as mechanical antennas, magnetometers, and radio frequency (RF) tunable inductors, which have been realized due to the strong strain-mediated magnetoelectric (ME) coupling found in ME composites. The development of single-phase multiferroic materials (which exhibit simultaneous ferroelectric and ferromagnetic or antiferromagnetic orders), multiferroic heterostructures, as well as progress in other ME mechanisms, such as electrostatic surface charging or magneto-ionics (voltage-driven ion migration), have a large potential to boost energy efficiency in spintronics and magnetic actuators. This article focuses on existing ME materials and devices and reviews the state of the art in their performance.

 

Schnelle et al

Magnetic and electronic ordering phenomena in the Ru2O6-layer honeycomb lattice compound AgRuO3

The silver ruthenium oxide AgRuO3 consists of honeycomb Ru25+O62− layers and can be considered and can be considered an analogue of SrRu2O6 with a different intercalation. We present measurements of magnetic susceptibility and specific heat on AgRuO3 single crystals, which reveal a sharp antiferromagnetic transition at 342(3) K. The electrical transport in single crystals of AgRuO3 is determined by a combination of activated conduction over an intrinsic semiconducting gap of ≈100 meV and carriers trapped and thermally released from defects.