Scientific Highlights
Electric-Field-Induced Skyrmion Distortion and Giant Lattice Rotation in the Magnetoelectric Insulator Cu2OSeO3
Discovering fundamentally new ways to manipulate magnetic spins is crucial for research into advanced technologies. Magnetic Skyrmions, which are topologically stable whirls of magnetic spins, are promising candidates for new device components since those found in metallic host materials can be manipulated using electric currents.
Controlling the near-surface superfluid density in under doped YBa2Cu3O6+x by photo-illumination
The interaction with light weakens the superconducting ground state in classical superconductors. The situation in cuprate superconductors is more complicated: illumination increases the charge carrier density, a photo-induced effect that persists below room temperature. Furthermore, systematic investigations in underdoped YBa2Cu3O6+x (YBCO) have shown an enhanced critical temperature Tc. Until now, studies of photo-persistent conductivity (PPC) have been limited to investigations of structural and transport properties, as well as the onset of superconductivity.
Low-temperature solid-oxide fuel cells based on proton-conducting electrolytes
The need for reducing the operating temperature of solid-oxide fuel cells (SOFCs) imposed by cost reduction has pushed significant progress in fundamental understanding of the individual components, as well as materials innovation and device engineering. Proton-conducting oxides have emerged as potential alternative electrolyte materials to oxygen-ion conducting oxides for operation at low and intermediate temperatures.
Plasma interactions determine the composition in pulsed laser deposited thin films
Plasma chemistry and scattering strongly affect the congruent, elemental transfer during pulsed laser deposition of target metal species in an oxygen atmosphere. Studying the plasma properties of La0.6Sr0.4MnO3, we demonstrate for as grown La0.6Sr0.4MnO3-δ films that a congruent transfer of metallic species is achieved in two pressure windows: ∼10−3 mbar and ∼2 × 10−1 mbar.
Mixed Dimensionality of Confined Conducting Electrons in the Surface Region of SrTiO3
Using angle-resolved photoemission spectroscopy, we show that the recently discovered surface state on SrTiO3 consists of nondegenerate t2g states with different dimensional characters.
A revealing mixture: The surface of an oxide insulator can host two distinct types of conducting electrons
Strontium titanate, SrTiO3, is an important material for the realization of next-generation electronic devices. A famous example is the interface of LaAlO3 grown on SrTiO3, which is metallic and magnetic at its interface, even though the individual compounds are insulating and nonmagnetic in bulk form. The physics behind how novel interface states form on SrTiO3 - and how they become endowed with such surprising properties - is not well understood.
Spin-lattice coupling induced weak dynamical magnetism in EuTiO3 at high temperatures
EuTiO3, which is a G-type antiferromagnet below TN = 5.5 K, has some fascinating properties at high temperatures, suggesting that macroscopically hidden dynamically fluctuating weak magnetism exists at high temperatures. This conjecture is substantiated by magnetic field dependent magnetization measurements, which exhibit pronounced anomalies below 200 K becoming more distinctive with increasing magnetic field strength. Additional results from muon spin rotation experiments provide evidence for weak fluctuating bulk magnetism induced by spin-lattice coupling which is strongly supported in increasing magnetic field.
Low-Temperature Micro-Solid Oxide Fuel Cells with Partially Amorphous La0.6Sr0.4CoO3-δ Cathodes
Partially amorphous La0.6Sr0.4CoO3-δ (LSC) thin-film cathodes are fabricated using pulsed laser deposition and are integrated in free-standing micro-solid oxide fuel cells (micro-SOFC) with a 3YSZ electrolyte and a Pt anode. A low degree of crystallinity of the LSC layers is achieved by taking advantage of the miniaturization of the cells, which permits low-temperature operation (300–450 °C).
Correlated Decay of Triplet Excitations in the Shastry-Sutherland Compound SrCu2(BO3)2
The temperature dependence of the gapped triplet excitations (triplons) in the 2D Shastry-Sutherland quantum magnet SrCu2(BO3)2 is studied by means of inelastic neutron scattering. The excitation amplitude rapidly decreases as a function of temperature, while the integrated spectral weight can be explained by an isolated dimer model up to 10 K.
Fast scanning coherent X-ray imaging using Eiger
The smaller pixel size, high frame rate, and high dynamic range of next-generation photon counting pixel detectors expedites measurements based on coherent diffractive imaging (CDI). The latter comprises methods that exploit the coherence of X-ray synchrotron sources to replace imaging optics by reconstruction algorithms. Researchers from the Paul Scherrer Institut have recently demonstrated fast CDI image acquisition above 25,000 resolution elements per second using an in-house developed Eiger detector. This rate is state of the art for diffractive imaging and even on a par with the fastest scanning X-ray transmission instruments. High image throughput is of crucial importance for both materials and biological sciences for studies with representative population sampling.