Scientific Highlights
Unconventional superconductivity found in kagome metal
Physicists using muon spin spectroscopy at PSI make the missing link between their recent breakthrough in Nature and unconventional superconductivity
X-ray tomography helps understand how the heart beats
Researchers at the Swiss Light Source SLS use X-ray phase contrast imaging to study a heart in action as it beats.
Updated electrochemical impedance model for understanding the interface of metallic lithium
Lithium metal negative electrodes are often used as counter electrodes while testing other electrochemically active materials, and are considered to be equivalent, independently of their thickness, supplier and production processes used. Here, we clearly demonstrate, using Electrochemical Impedance spectroscopy (EIS) that it is not the case, as well as the often-used symmetric cells are actually not so symmetric, when EIS spectra are disentangled using Thee-electrode cells.
CHART MagDev CCT Dipole achieves record field
As one of the first CHART projects, the MagDev activity at PSI designed and built a canted-cosine theta (CCT) demonstrator magnet, wound from Nb3Sn conductor.
Solidification modes during additive manufacturing
The thermal conditions during laser-based additive manufacturing are inferred from high-speed X-ray diffraction data and can be linked to a model for rapid solidification.
PLD plasma plume analysis, a summary of the PSI contribution
We report on the properties of laser-induced plasma plumes generated by ns pulsed excimer lasers as used for pulsed laser deposition to prepare thin oxide films. A focus is on the time and spatial evolution of chemical species in the plasma plume as well as the mechanisms related to the plume expansion. The overall dynamics of such a plume is governed by the species composition in particular if three or more elements are involved. We studied the temporal evolution of the plume, the composition of the chemical species in the plasma, as well as their electric charge. In particular, ionized species can have an important influence on film growth. Likewise, the different oxygen sources contributing to the overall oxygen content of an oxide film are presented and discussed. Important for the growth of oxide thin films is the compositional transfer of light element such as oxygen or Li. We will show and discuss how to monitor these light elements using plasma spectroscopy and plasma imaging and outline some consequences of our experimental results.
Fate of charge order in overdoped La-based cuprates
In high-temperature cuprate superconductors, stripe order refers broadly to a coupled spin and charge modulation with a commensuration of eight and four lattice units, respectively. How this stripe order evolves across optimal doping remains a controversial question. Here we present a systematic resonant inelastic x-ray scattering study of weak charge correlations in La2−xSrxCuO4 and La1.8−xEu0.2SrxCuO4. Ultra high energy resolution experiments demonstrate the importance of the separation of inelastic and elastic scattering processes. Long-range temperature-dependent stripe order is only found below optimal doping. At higher doping, short-range temperature-independent correlations are present up to the highest doping measured. This transformation is distinct from and preempts the pseudogap critical doping. We argue that the doping and temperature-independent short-range correlations originate from unresolved electron–phonon coupling that broadly peaks at the stripe ordering vector. In La2−xSrxCuO4, long-range static stripe order vanishes around optimal doping and we discuss both quantum critical and crossover scenarios.
Fate of charge order in overdoped La-based cuprates
In high-temperature cuprate superconductors, stripe order refers broadly to a coupled spin and charge modulation with a commensuration of eight and four lattice units, respectively. How this stripe order evolves across optimal doping remains a controversial question. Here we present a systematic resonant inelastic x-ray scattering study of weak charge correlations in La2−xSrxCuO4 and La1.8−xEu0.2SrxCuO4. Ultra high energy resolution experiments demonstrate the importance of the separation of inelastic and elastic scattering processes.
Making the most of our data
New initiatives will develop open data practices in key strategic areas including electron microscopy and materials science at Paul Scherrer Institute PSI.
Unusual ferrimagnetism in CaFe2O4
Rare ferrimagnet states in a phase competing antiferromagnet.