Highlights of PSI-FELLOW Collaborations resulting in Publications
On the way to intelligent microrobots
It is reminiscent of a paper bird made with the help of the Japanese folding art origami: a microrobot that uses the force of magnetic fields to move. In the future, such small machines could be used, for example, in medical operations.
Preventing tumour metastasis
Researchers at the Paul Scherrer Institute PSI, together with colleagues from the pharmaceutical company F. Hoffmann-La Roche AG, have taken an important step towards the development of an active substance against the metastasis of certain cancers. Using the Swiss Light Source SLS, they deciphered the structure of a receptor that plays a crucial role in the migration of cancer cells.
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.
Magnetically Addressable Shape-Memory and Stiffening in a Composite Elastomer
With a specific stimulus, shape‐memory materials can assume a temporary shape and subsequently recover their original shape, a functionality that renders them relevant for applications in fields such as biomedicine, aerospace, and wearable electronics. Shape‐memory in polymers and composites is usually achieved by exploiting a thermal transition to program a temporary shape and subsequently recover the original shape.
Chirally coupled nanomagnets
Magnetically coupled nanomagnets have multiple applications in nonvolatile memories, logic gates, and sensors. The most effective couplings have been found to occur between the magnetic layers in a vertical stack. We achieved strong coupling of laterally adjacent nanomagnets using the interfacial Dzyaloshinskii-Moriya interaction. This coupling is mediated by chiral domain walls between out-of-plane and in-plane magnetic regions and dominates the behavior of nanomagnets below a critical size.
Photoswitching in a Molecular Cube
Niéli’s paper is accepted in the Journal of Physical Chemistry Letters! We use X-ray absorption spectroscopy and X-ray magnetic circular dichroism to watch directly how the Co and Fe ions in a molecular cube change their oxidation states and turn from diamagnetic into paramagnetic units upon light irradiation.
New Method for Calculating Soft X-ray Magnetic Circular Dichroism Spectra
Scientists have demonstrated in a combined theoretical and experimental effort that the new ligand-field density functional theory method (LF-DFT) can be used to calculate the X-ray absorption spectra (XAS) and X-ray magnetic circular dichroism (XMCD) of lanthanide compounds from purely structural input.
Electronic localization in CaVO3 films via bandwidth control
Understanding and controlling the electronic structure of thin layers of quantum materials is a crucial first step towards designing heterostructures where new phases and phenomena, including the metal-insulator transition (MIT), emerge. Here, we demonstrate control of the MIT via tuning electronic bandwidth and local site environment through selection of the number of atomic layers deposited.