Forschung zu Covid-19

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.

Magnetic skyrmions are well-suited for encoding information because they are nano-sized, topologically stable, and only require ultra-low critical current densities j_c to depin from the underlying atomic lattice. Above j_c, 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 j_c as predicted by theory.

Magnetic skyrmion is a topologically protected particle-like object in magnetic materials, appearing as a nanometric swirling spin texture. The size and shape of skyrmion particles can be flexibly controlled by external stimuli, which suggests unique features of their crystallization and lattice transformation process. Here, we investigated the detailed mechanism of structural transition of skyrmion lattice (SkL) in a prototype chiral cubic magnet Cu₂OSeO₃, by combining resonant soft X-ray scattering (RSXS) experiment and micromagnetic simulation...

During the past decade, scientists have put high effort to achieve sub-10 nm resolution in X-ray microscopy. Recent developments in high-resolution lithography-based diffractive optics, combined with the extreme stability and precision of the PolLux and HERMES scanning X-ray microscopes, resulted now in a so far unreached resolution of seven nanometers in scanning soft X-ray microscopy. Utilizing this highly precise microscopy technique with the X-ray magnetic circular dichroism effect, dimensionality effects in an ensemble of interacting magnetic nanoparticles can be revealed.

Ricarda Nebling, PhD student at LMN, received a prize at the SPIE Extreme Ultraviolet Conference 2020 for her contribution: “Effects of the illumination NA on EUV mask inspection with coherent diffraction imaging”.

Quantum materials have properties that defy conventional theories of solids. Explaining these unusual properties is a frontier in physics, which promises both technological applications and fundamentally new states of matter. Yb₂Ti₂O₇ is a center of attention in this work. While it becomes ferromagnetic at very low temperature, its excitation spectrum resembles that of a quantum spin liquid. We show using neutron scattering ...

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.

Non-centrosymmetric superconductors (NCSCs) are promising candidates in the search for unconventional and topological superconductivity. The α-Mn-type rhenium-based alloys represent excellent examples of NCSCs, where spontaneous magneticfields, peculiar to time-reversal symmetry (TRS) breaking, have been shown to develop in the superconducting phase. By converse, TRS is preserved in many other isostructural NCSCs, thus leaving the key question about its origin fully open. Here, we consider ...