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Scientists, publishing in Nature, have found that a hybrid antimatter-matter atom behaves in an unexpected way when submerged in superfluid helium.

Spin glasses, generally defined as disordered systems with randomized competing interactions, are a widely investigated complex system. Theoretical models describing spin glasses are broadly used in other complex systems, such as those describing brain function, error-correcting codes or stock-market dynamics. This wide interest in spin glasses provides strong motivation to generate an artificial spin glass within the framework of artificial spin ice systems. Here we present the experimental realization of an artificial spin glass consisting of dipolar coupled single-domain Ising-type nanomagnets arranged onto an interaction network that replicates the aspects of a Hopfield neural network.

Prediction of the mechanical properties dictated by the local microfiber orientation is essential for the performance characterization of fiber-reinforced composites. Typically, tomographic imaging methods that provide fine spatial resolution are employed to investigate various materials' local micro- and nano-architecture in a non-destructive manner. However, conventional imaging techniques are limited by a substantial trade-off between the structure size of interest and the accessible field of view (FOV). Researchers from the TOMCAT beamline at Paul Scherrer Institut, Xnovo Technology ApS, and the Technical University of Denmark have demonstrated the potential of X-ray scattering tensor tomography for industrial applications by characterizing the microstructure of a centimeter-sized industrially relevant freeform injection molding fiber-reinforced composite sample. This emerging technique provides unprecedented access to microstructural information over centimeter-sized sample volumes paving the way towards its potential integration as an invaluable tool, for instance, in the fiber-reinforced-composite (FRC) industry. The obtained fiber orientation and anisotropy information over statistically relevant large volumes can be used to predict the mechanical properties of final products, optimize production parameters, and improve fiber injection molding simulation frameworks. The work is published in Composites Part B: Engineering on 15 March 2022.

Operando time-resolved V and Ti K-edge X-ray absorption near-edge spectroscopy, coupled with a transient experimental strategy, quantitatively showed that the formation of acetaldehyde over 5% V₂O₅/15% TiO₂/SiO₂ is kinetically coupled to the formation of a V⁴⁺ intermediate, while the formation of V³⁺ is delayed and 10–70 times slower. The low-coordinated nature of various redox states of VO_x species (V⁵⁺, V⁴⁺, and V³⁺) in the 5% V₂O₅/15% TiO₂/SiO₂ catalyst is confirmed using the extensive database of V K-edge XANES spectra of standards and specially synthesized molecular crystals.

A novel approach to controlling the speed of magnetic processes has been found through resonant magnetic scattering in an antiferromagnetic Lanthanide intermetallics.

Researchers at PSI have refined the theoretical prediction for the pair production of Higgs bosons at the LHC and re-analized the related uncertainties resulting in sizable contributions neglected before. This process will be highly relevant at the high-luminosity run of the LHC to measure the Higgs potential directly.

Just as electrons flow through an electrical conductor, magnetic excitations can travel through certain materials. Such excitations, known in physics as "magnons" in analogy to the electron, could transport information much more easily than electrical conductors. An international research team has now made an important discovery on the way towards such components, which could be highly energy-efficient and considerably smaller.

Measurement of the absolute value of the applied pressure in high-pressure muon and neutron experiments is a complicated task. It often requires the presence of a calibration material inside the sample volume, and could also cause additional time to obtain the response of the calibrant. Here we describe the use of optical calibrants for precise determination of the pressure value inside the piston-cylinder clamp cells.

Our French collaborators and CNRS produced an excellent short movie about our common n2EDM experiment. The apparatus is currently being set up in

UCN Area South. The collaboration is on track for commissioning of the apparatus with neutrons towards the end of 2022.

We present a study of Cu-substitution effects in 4f-Ce intermetallic compound CeAu_1-xCu_xGe, with potentially unusual electronic states, in the whole concentration range (x = 0.0 – 1.0). The parent CeAuGe compound, crystallizing in a non-centrosymmetric hexagonal structure, is a ferromagnetic semimetal with Curie temperature 10 K. Cu-doping on Au-site of CeAuGe, CeAu_1-xCu_xGe, changes the crystal structure from the non-centrosymmetric (P6₃mc) to centrosymmetric (P6₃/mmc) space group at the concentration x ∼ 0.5, where the c-lattice constant has a maximum value. Magnetic susceptibility and electrical resistivity measurements reveal that all Cu-doped compounds undergo magnetic phase transition near 10 K, with the maximum transition temperature of 12 K for x = 0.5. The neutron powder diffraction experiments show the ferromagnetic ordering of Ce³⁺ magnetic moments with a value of about 1.2 μ_B at 1.8 K, oriented perpendicular to the hexagonal c-axis. By using symmetry analysis, we have found the solutions for the magnetic structure in the ferromagnetic Shubnikov space groups Cmc'2₁′ and P2₁′/m' for x < 0.5 and x ≥ 0.5, respectively. Electrical resistivity ρ(T) exhibits a metallic temperature behaviour in all compositions. The resistivity ρ(T) has a local minimum in the paramagnetic state due to Kondo effects at high doping x = 0.8 and 1.0. At the small Cu-doping level, x  = 0.2, the resistivity shows a broad feature at the ferromagnetic transition temperature and an additional transition-like peculiarity at 2.5 K in the ferromagnetic state.