LNS - Scientific Highlights
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.
Auto-Bremsen weiter optimieren
Mit Neutronen blicken Forschende des PSI und ANAXAM ins Innere einer Bremse und spüren Potenziale zur Senkung von CO2-Emissionen auf.
Single-domain stripe order in a high-temperature superconductor
The coupling of spin, charge and lattice degrees of freedom results in the emergence of novel states of matter across many classes of strongly correlated electron materials. A model example is unconventional superconductivity, which is widely believed to arise from the coupling of electrons via spin excitations. In cuprate high-temperature superconductors, the interplay of charge and spin degrees of freedom is also reflected in a zoo of charge and spin- density wave orders that are intertwined with superconductivity ...
Emergence of spinons in layered trimer iridate Ba4Ir3O10
Spinons are well-known as the elementary excitations of one-dimensional antiferromagnetic chains, but means to realize spinons in higher dimensions is the subject of intense research. Here, we use resonant x-ray scattering to study the layered trimer iridate Ba4Ir3O10, which shows no magnetic order down to 0.2 K. An emergent one-dimensional spinon continuum is observed that can be well-described by XXZ spin-1/2 chains with magnetic exchange of ∼55 meV and a small Ising-like anisotropy. With 2% isovalent Sr doping ...
Graphene’s magic in a magnet
Neutron scattering reveals rich magnetic topology in the magnetic equivalent of graphene.
Three PSI research facilities reveal magnetic crossover
Insights from the Swiss Muon Source, Swiss Spallation Neutron Source and Swiss Light Source reveal this coveted characteristic in an exotic layered material.
Spin Density Wave versus Fractional Magnetization Plateau in a Triangular Antiferromagnet
We report an excellent realization of the highly nonclassical incommensurate spin-density wave (SDW) state in the quantum frustrated antiferromagnetic insulator Cs2CoBr4. In contrast to the well-known Ising spin chain case, here the SDW is stabilized by virtue of competing planar in-chain anisotropies and frustrated interchain exchange.
Dynamic magnetic crossover at the origin of the hidden-order in van der Waals antiferromagnet CrSBr
The van-der-Waals material CrSBr stands out as a promising two-dimensional magnet. Here, we report on its detailed magnetic and structural character- istics. We evidence that it undergoes a transition to an A-type anti- ferromagnetic state below TN ≈ 140 K with a pronounced two-dimensional character, preceded by ferromagnetic correlations within the monolayers. Furthermore, we unravel the low-temperature hidden-order within the long- range magnetically-ordered state. We find that it is associated to a slowing down of the magnetic fluctuations, accompanied by a continuous reorienta- tion of the internal field.
Dipolar spin-waves and tunable band gap at the Dirac points in the 2D magnet ErBr3
Topological magnon insulators constitute a growing field of research for their potential use as information carriers without heat dissipation. We report an experimental and theoretical study of the magnetic ground-state and excitations in the van der Waals two-dimensional honeycomb magnet ErBr3. We show that the magnetic properties of this compound are entirely governed by the dipolar interactions which generate a continuously degenerate non-collinear ground-state on the honeycomb lattice with spins confined in the plane.