Three-dimensional magneto-dynamical processes give rise to rich dynamical behavior and might enable novel functionalities for devices. However, in imaging experiments such processes can be typically characterized only indirectly, not least as there is no technique available for resolving the dynamics both in time and along all three spatial dimensions. That is, until now. A team led by PSI researchers, working at the PolLux endstation of SLS, has combined pump–probe STXM imaging with soft X-ray magnetic laminography. With this approach they are able to resolve magnetization dynamics in four dimensions, as they exemplified in an investigation of two resonant dynamical modes of a CoFeB microstructure. For X-ray detection, an avalanche photodiode is used, which means that excitations of arbitrary frequencies can be studied — thereby overcoming a major limitation of current techniques in which the acquisition of single projections relies on two-dimensional X-ray detectors.

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Magnesium-metal batteries are promising candidates for future energy-storage devices beyond the well-established Li-ion technologies. However, progress towards a competitive magnesium battery is hindered by a lack of efficient and stable Mg-ion electrolytes. An international team of researchers now reports a novel route to boosting conductivity in the solid-state electrolyte Mg(BH₄)₂·1.6NH₃, which has emerged as a promising material for operation at practically relevant temperatures. Combining several characterization methods, including quasielastic neutron scattering (QENS) measurements performed at the time-of-flight spectrometer FOCUS of SINQ, the team demonstrates that adding insulating Al₂O₃ nanopowder to Mg(BH₄)₂·1.6NH₃ can substantially improve the ionic conductivity, in particular at room temperature. Moreover, the QENS analysis revealed a similar activation energy for Mg-ionic migration and NH₃ rotations — suggesting a mechanism how the neutral NH₃ molecules assist Mg²⁺ migration.

In recent years, there has been growing interest in 4d/5d transition-metal systems, fueled by observations of novel spin–orbit-coupled states. A prime example is the so-called J_eff= ½ state in honeycomb iridate materials and α-RuCl₃, which has been shown to drive Kitaev interactions. An international team of researchers now introduce a new spin–orbital state in a honeycomb structure — one that drives Ising instead of Kitaev interactions. The new state emerges through restructuring the spin–orbital wave functions by tuning the interplay between spin–orbit interaction and trigonal crystal field, as achieved in a topochemical reaction converting Li₂RhO₃ to Ag₃LiRh₂O₆. By combining first-principles calculations with magnetization measurements, muon spin relaxation — performed at SμS — and X-ray absorption spectroscopy, the team establishes that their system provides the first example of successful tuning between the Kitaev and Ising limits in the same material family.

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Organic light-emitting diodes (OLEDs) have become ‘must-have’ displays for consumer goods, from handheld smartphones to large-area TV screens. Unsurprisingly, further developments are in the pipeline. The newest generation of OLED emitters is based on coordination entities with abundant, inexpensive metal centers, mainly copper. PSI beamline scientist Grigory Smolentsev and Matthias Vogt from the University of Halle-Wittenberg now discuss in a review article how time-resolved X-ray spectroscopy can provide unique insight into such luminophores based on metal complexes. In particular, determining their excited-state structures is important, for understanding non-radiative losses. Such insight, in turn, should help to develop more efficient luminophores. Among different time-resolved techniques, they focus on methods using synchrotron radiation that cover the time range from 100 ps to microseconds, and highlight first results and perspectives of experiments using X-ray free electron lasers. 

An international team of scientists has laid the groundwork for a dedicated experiment to search for the muon electric dipole moment (EDM) at PSI. This search will provide insight into the violation of charge–parity symmetry in muons, and could corroborate hints for new physics observed in the muon g-2 and semileptonic B-decays. In 2020, researchers from more than 20 institutions discussed at PSI key ideas for a novel experiment based on the frozen-spin technique. A year later, the CHRISP research committee welcomed the letter of intent, submitted by the initiative. Now, boosted by an ERC Consolidator grant awarded to Dr. Philipp Schmidt-Wellenburg, the members of the future collaboration met in May 2022 in Pisa. In an initial phase, the collaboration strives to implement the frozen-spin technique in a compact solenoid, with the goal of demonstrating a 30-times higher sensitivity to the muon EDM than in any previous experiment. Prospects for further improvements include in particular the use of the new high-intensity muon beams at PSI (HIMB).
 

In the week of 21–25 March 2022, we had the pleasure of welcoming online 20 international PhD students, postdocs and scientists for the Hercules School on Neutrons and Synchrotron Radiation. The participants attended online lectures, virtual tours and remote practicals given by SLS, SINQ and SμS staff. The school is dedicated to introducing scientists to new techniques and methods at large-scale facilities utilizing photons, neutrons and muons, and covers multiple disciplines, including biology, chemistry, physics, material science and industrial applications. 
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PSI researchers report first imaging experiments performed with a 25 μm pixel pitch GaAs:Cr sensor of 500 μm thickness bump-bonded to the charge-integrating MÖNCH 03 readout chip developed at PSI. In experiments at the TOMCAT beamline of SLS, carried out in the energy range of 10–30 keV, a spatial resolution of ∼5 μm was obtained at 16 keV when applying a suitable interpolation algorithm. These are promising results that point to new possibilities for imaging experiments at photon energies above 15 keV, where silicon sensors suffer from a diminishing quantum efficiency. 
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Soon the first users will benefit from the collaboration between the Laboratoire Léon Brillouin (LLB, Saclay, France) and PSI, which will jointly operate a small-angle neutron scattering (SANS) instrument at SINQ. The SANS-LLB instrument, formerly known as PA20 at LLB, is reaching its final commissioning stages. SANS-LLB mainly consists of the state-of-the-art instrumentation of PA20. However, to adapt to the new neutron source and to the sample environments available at PSI, the polarizer, the collimation and the sample table were updated. SANS-LLB expects to receive its first friendly users in the second half of 2022, and to join the user program in 2023. A French-Swiss Meeting “SANS for Soft Matter” was organized jointly by the PSI-LLB team in Strasbourg/France, attracting many scientists eager to use SANS-LLB.
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The latest submission deadline for SμS beamtime applications passed on 7 June. Again a strong demand for muon beamtime at PSI was recognized: in total 88 new proposals were submitted that asked for 422 days all together. The call was open on four instruments and the highest demand was again for GPS beamtime, with 48 proposals (132 days). The remaining 40 proposals distribute almost equally over HAL-9500 (15), LEM (14) and GPD (11). The proposals are now under evaluation and we aim to send out the results to our users by the end of July.

Free-electron lasers (FELs) deliver brilliant, ultrashort and coherent X-ray pulses that enable unique investigations of dynamics at the inherent time and length scale of atoms. A full exploitation of the coherence properties requires, however, the generation of coherent copies of X-ray pulses, which would facilitate a realm of X-ray techniques analogous to those currently only available with optical laser light. Now, PSI researchers have devised an X-ray beam splitter that produces two perfectly coherent copies of pulses, and discuss prospects for time-domain interferometry and quantum optics exploiting FELs. 
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The high-intensity ultracold neutron (UCN) source at PSI is in user operation since 2011. Detailed studies of all components have been performed over the years, leading to significant performance improvements. A new publication summarizes two key measurements concerning the UCN transport from neutron production to experiment and their simulation-based analysis. In one measurement, every five minutes a few thousand UCNs were stored in a bottle and sent through the central storage volume over ~16 m of UCN guides. The other measurement charted the height-dependent UCN density, so that experiments can be optimally positioned.
As some components of the UCN source are aging, a project to provide a new deuterium insert (UCN 2.0) is being started. Based on our acquired knowledge of UCN transport and source operation, improvements to the deuterium moderator vessel, central shutters, UCN guiding and temperature control can be implemented, aiming also to improve UCN intensity.
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