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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PSI scientist Thorsten Schmitt (left) and post-doc Kejin Zhou (right) at the RIXS measuring station of the ADRESS beamline at SLS, where they are inserting a sample into the measuring apparatus. Here, X-rays are used for investigating materials with very high precision. (Photo: Scanderbeg Sauer Photography)

Physicists observe the splitting of an electron inside a solid

An electron has been observed to decay into two separate parts, each carrying a particular property of the electron: a spinon carrying its spin – the property making the electron behave as a tiny compass needle – and an orbiton carrying its orbital moment – which arises from the electron’s motion around the nucleus. These newly created particles, however, cannot leave the material in which they have been produced.

Ellipsoidal hybrid magnetic microgel particles with thermally tunable aspect ratios

We report on the synthesis and characterization of multiresponsive hybrid microgel particles. The particles consist of ellipsoidal silica-coated maghemite cores subsequently coated with thermoresponsive poly (N-isopropylacrylamide) (PNIPAM) shells. The PNIPAM shell enables the hybrid particle to alter its size and ratio of long to small axis with increasing temperature while the core morphology remains unchanged.

PSI-Feriencamp 2012

Suchen Sie für Ihr Kind ein spannendes Angebot während den Sommerferien? Möchten Sie in ihm die Neugier und Begeisterung für naturwissenschaftlich-technische Themen wecken? Die Berufsbildung und das Komitee für Chancengleichheit führt dieses Jahr zum achten Mal das PSI-Feriencamp durch!

Fig.1: Non-magnetic state of iron-rhodium (FeRh) when illuminated by a laser pulse

Creating magnetism takes much longer than destroying it

Researchers at the Paul Scherrer Institute are finding out how long it takes to establish magnetism and how this happens.

Structural and magnetic dynamics of a first order phase transition

We use time-resolved x-ray diffraction and magneto-optical Kerr effect to study the laser-induced antiferromagnetic to ferromagnetic phase transition in FeRh. The structural response is given by the nucleation of independent ferromagnetic domains (t ~ 30 ps).

Directly coupled Ferromagnetism and Ferroelectricity in the Olivine Mn2GeO4

The olivine compound Mn2GeO4 is shown to feature both a ferroelectric polarization and a ferromagnetic magnetization that are directly coupled and point along the same direction. We show that a spin spiral generates ferroelectricity, and a canted commensurate order leads to weak ferromagnetism.

(a) Spins align antiparallel to each other, resulting in a large lattice strain and large electric polarization. (b) Spins align helically along the b-axis, resulting in small electric polarization.

Origin of the Large Polarization in Multiferroic YMnO3 Thin Films

Multiferroic materials have attracted much interest because of their ability to control magnetism by the application of an electric field. This ability is expected to reduce the power required by electronic devices and to increase their speed. However, the number of multiferroic materials discovered so far has been small, and ferromagnetism and ferroelectricity in the known materials are often much weaker than required for practical applications.

Effect of hard-sphere fluid confinementon pair correlations represented byexperimental (top) and theoretical (bottom) anisotropic structure factors. Channel widths increase from left to right.

Liquids in narrow spaces

How does spatial confinement affect the microscopic structure of liquids?

This is a question which is receiving increasing attention from condensed matter physicists. Liquids are characterized by a short-ranged, so-called local structure, and it has been predicted theoretically about 25 years ago that confinement induces anisotropy in the local structure, and hence many properties, of liquids.

Femtosecond dynamics of an antiferromagnetic phase transition

We report on the ultrafast dynamics of magnetic order in a single crystal of CuO at a temperature of 207 K in response to strong optical excitation using femtosecond resonant x-ray diffraction. In this experiment performed at the LCLS X-ray free electron laser at Stanford a femtosecond laser pulse induces a sudden, nonequilibrium increase in magnetic disorder.

Heavy-fermion metal YbRh2Si2: f-derived Fermi surface and fine dispersion of CEF 4f bands in particular parts of the k-space

A close look at correlated electrons in heavy-fermion metal through ARPES

Showing astonishing properties like magnetism, superconductivity, Kondo and heavy-fermion (HF) behavior, rare-earth intermetallic compounds have been at the forefront of modern solid state physics for many years. Most of these properties are related to a delicate interplay between the partially filled 4f-shell and conduction electrons.

Beam cross section in comparison to a human hair

Vertical Emittance of the SLS Storage Ring

On the 6th of December 2011 the vertical emittance of the SLS storage ring could be reduced to a world record low value of 1pm rad. The vertical beam size in the short straight sections of the SLS is then only 3 micron (rms). This was achieved through vertical re-alignment of the magnet girders with 400mA stored beam and fast orbit feedback running, as well as through application of several different methods of coupling suppression using 36 skew quadrupoles. High resolution profile monitor utilizing vertically polarized component of synchrotron radiation allowed precise determination of the beam size.

Model of the eukaryotic ribosome (taken from Klinge et al.)

New insights into the cell’s protein factory

Eukaryotic ribosomes are among the most complex cellular machineries of the cell. These large macromolecular assemblies are responsible for the production of all proteins and are thus of pivotal importance to all forms of life. Two independent research groups at the ETH Zürich and the Institute of Genetics and Molecular and Cellular Biology in Strasbourg have obtained new insights into the atomic structure of the eukaryotic ribosome. The results have been published in the journal Science.

Angle-resolved Photoemission (ARPES) on bilayer system La2-2xSr1+2xMn2O7

Bilayer manganites reveal polarons in the midst of a metallic breakdown

The origin of colossal magnetoresistance (CMR) in manganese oxides is among the most challenging problems in condensed- matter physics today. The true nature of the low-temperature electronic phase of these materials is heavily debated. By combining photoemission and tunnelling data, we show that in the archetypal bilayer system La2-2xSr1+2xMn2O7, polaronic degrees of freedom win out across the CMR region of the phase diagram.