Scientific Highlights
Designing the stripe-ordered cuprate phase diagram through uniaxial-stress
Understanding the degree to which charge-stripe, spin-stripe, and superconducting orders compete/coexist is paramount for elucidating the microscopic pairing mechanism in the cuprate high-temperature superconductors. We explore the tunability of magnetism, superconductivity, and crystal structure in the stripe phase of the cuprate La2−xBaxCuO4, by employing complementary techniques under compressive uniaxial stress in the CuO2 plane. Our results show a sixfold increase ...
Climate-neutral aviation: will it fly?
The European aviation sector stands at a pivotal juncture in its quest to achieve net-zero climate impacts. Focusing on flight CO2 emissions overlooks up to 80% of the sector's climate repercussions.
Our research delves deep into the role of electricity-based synthetic jet fuels and direct air carbon capture and storage (DACCS) as potential game-changers. These solutions promise climate-neutral aviation, but there's a catch: the relentless rise in air traffic. Relying solely on renewables-derived synthetic fuels may strain both economic and natural resources. On the flip side, offsetting fossil jet fuel impacts via DACCS poses its own set of challenges. Our findings underscore one clear message: for a genuinely climate-neutral European aviation, we must reconsider the scale of air traffic.
Quantification of PEFC Catalyst Layer Saturation via Small-Angle X‑ray Scattering
The complex nature of liquid water saturation in polymer electrolyte fuel cell (PEFC) catalyst layers (CLs) greatly affects the device performance. To investigate this problem, a method to quantify the presence of liquid water in a PEFC CL using small-angle X-ray scattering (SAXS) was developed in a collaboration of researchers of the Federal Institute for Materials Research and Testing (BAM, Berlin, Germany), the Photon Science Division and the Electrochemistry Laboratory of PSI. The method leverages the differences in electron densities between the solid catalyst matrix and the CL-pores filled with liquid water under dry and wet conditions, respectively.
Dichotomous Electrons: Travelling without Moving
Neutron scattering experiments give new understanding of how localized and free-flowing electrons collaborate to create material functionality.
Tetrahedral triple-Q magnetic ordering and large spontaneous Hall conductivity in the metallic triangular AFM Co1/3TaS2
The triangular lattice antiferromagnet (TLAF) has been the standard paradigm of frustrated magnetism for several decades. The most common magnetic ordering in insulating TLAFs is the 120° structure. However, a new triple-Q chiral ordering can emerge in metallic TLAFs, representing the short wave- length limit of magnetic skyrmion crystals. We report the metallic TLAF Co1/3TaS2 as the first example of tetrahedral triple-Q magnetic ordering with the associated topological Hall effect (non-zero σxy(H = 0)). We also ...
Phonon Topology and Winding of Spectral Weight in Graphite
The topology of electronic and phonon band structures of graphene is well studied and known to exhibit a Dirac cone at the K point of the Brillouin zone. Here, we applied inelastic x-ray scattering (IXS) along with ab initio calculations to investigate phonon topology in graphite, the 3D analog of graphene. We identified a pair of modes that form a very weakly gapped linear anticrossing at the K point that can be essentially viewed as a Dirac cone approximant. The IXS intensity ...
SwissFEL: a next generation tool for Attosecond Science
The 2023 Nobel Prize in Physics recognises attosecond science’s pioneers. Past and future, this field’s evolution is entwined with SwissFEL.
Listening for Defects as They Happen
Experiments at the Swiss Light Source SLS help resolve a long-standing debate surrounding metal 3D laser printing.
Skyrmion metamorphosis: Lattice transitions of hybrid skyrmions in a polar magnet
Magnetic skyrmions, with their distinctive vortex-like magnetic spin configurations, continue to intrigue researchers due to their potential applications in nanoscience and technology. Traditionally skyrmions form two-dimensional hexagonal close-packed lattices, with the skyrmions themselves displaying one of just two types of internal magnetization texture known as Bloch- or Néel-type. Recent theories hinted at the prospect of reconfigurable transitions between skyrmion phases of different lattice types and internal textures. Until now, experimental evidence supporting such theories has been scarce.
In-Plane Magnetic Penetration Depth in Sr2 RuO4 : Muon-Spin Rotation and Relaxation Study
We report on measurements of the in-plane magnetic penetration depth (λab) in single crystals of Sr2RuO4 down to ≃0.015 K by means of muon-spin rotation-relaxation. The linear temperature dependence of λ−2ab for T≲0.7 K suggests the presence of nodes in the superconducting gap. This statement is further substantiated by observation of the Volovik effect, i.e., the reduction of λ−2ab as a function of the applied magnetic field. The experimental zero-field ...