A5087693024- Physics of Superconductivity and Magnetism
- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Electronic and Structural Properties of Oxides
- Magnetic properties of thin films
- Iron-based superconductors research
- Multiferroics and related materials
- High-pressure geophysics and materials
- Rare-earth and actinide compounds
- Superconducting Materials and Applications
- Theoretical and Computational Physics
- Superconductivity in MgB2 and Alloys
- Advanced Chemical Physics Studies
- Ferroelectric and Piezoelectric Materials
- Nuclear Physics and Applications
- Inorganic Fluorides and Related Compounds
- Atomic and Subatomic Physics Research
- Quantum, superfluid, helium dynamics
- Copper-based nanomaterials and applications
- Advanced Thermoelectric Materials and Devices
- Inorganic Chemistry and Materials
- ZnO doping and properties
- Quantum and electron transport phenomena
- Transition Metal Oxide Nanomaterials
- Semiconductor materials and devices
Max Planck Institute for Solid State Research
2016-2025
Center for Integrated Quantum Science and Technology
2021-2024
RIKEN
2020
Superconducting and other Innovative Materials and Devices Institute
2017
Max Planck Institute for the Structure and Dynamics of Matter
2017
Diamond Light Source
2017
University of Oxford
2017
SLAC National Accelerator Laboratory
2017
Linac Coherent Light Source
2017
Max Planck Institute for Physics
2016
There are increasing indications that superconductivity competes with other orders in cuprate superconductors, but obtaining direct evidence bulk-sensitive probes is challenging. We have used resonant soft x-ray scattering to identify two-dimensional charge fluctuations an incommensurate periodicity of $\bf \sim 3.2$ lattice units the copper-oxide planes superconductors (Y,Nd)Ba$_2$Cu$_3$O$_{6+x}$ hole concentrations $0.09 \leq p 0.13$ per planar Cu ion. The intensity and correlation length...
We report a comprehensive neutron-scattering study of the evolution magnetic excitations in ${\mathrm{La}}_{2\mathrm{\ensuremath{-}}\mathit{x}}$${\mathrm{Sr}}_{\mathit{x}}$${\mathrm{CuO}}_{4}$ for 0\ensuremath{\le}x\ensuremath{\le}0.04. first present accurate measurements correlation length and sublattice magnetization carrier-free ${\mathrm{La}}_{2}$${\mathrm{CuO}}_{4}$ crystal analyze these context recent theoretical predictions. then systematically investigate influence different dopants...
The understanding of the origin superconductivity in cuprates has been hindered by apparent diversity intertwining electronic orders these materials. We combined resonant x-ray scattering (REXS), scanning-tunneling microscopy (STM), and angle-resolved photoemission spectroscopy (ARPES) to observe a charge order that appears consistently surface bulk, momentum real space within one cuprate family, Bi <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow>...
Electronic phases with symmetry properties matching those of conventional liquid crystals have recently been discovered in transport experiments on semiconductor heterostructures and metal oxides at millikelvin temperatures. We report the spontaneous onset a one-dimensional, incommensurate modulation spin system high-transition-temperature superconductor YBa 2 Cu 3 O 6.45 upon cooling below ∼150 kelvin, whereas static magnetic order is absent above kelvin. The evolution this temperature...
Orbital reconstructions and covalent bonding must be considered as important factors in the rational design of oxide heterostructures with engineered physical properties. We have investigated interface between high-temperature superconducting (Y,Ca)Ba 2 Cu 3 O 7 metallic La 0.67 Ca 0.33 MnO by resonant x-ray spectroscopy. A charge about –0.2 electron is transferred from Mn to ions across induces a major reconstruction orbital occupation symmetry interfacial CuO layers. In particular, d z – r...
The competition between collective quantum phases in materials with strongly correlated electrons depends sensitively on the dimensionality of electron system, which is difficult to control by standard solid-state chemistry. We have fabricated superlattices paramagnetic metal lanthanum nickelate (LaNiO(3)) and wide-gap insulator aluminate (LaAlO(3)) atomically precise layer sequences. used optical ellipsometry low-energy muon spin rotation show that LaNiO(3) as thin two unit cells undergo a...
A phase transition brought on by quantum fluctuations at absolute zero may seem like an abstract theoretical idea of little practical consequence. But it is the key to explaining a wide variety experiments.
We report the results a comprehensive study of charge density wave (CDW) correlations in untwinned YBCO6+x single crystals with 0.4<x<0.99 using Cu-L3 edge resonant x-ray scattering (RXS). Evidence CDW formation is found for 0.45<x<0.93, but not samples x<0.44 that exhibit incommensurate spin-density-wave order, and slightly overdoped x=0.99. This suggests presence two proximate zero-temperature critical points at doping pc1~0.08 pc2~0.18. The reflections are observed in-plane vectors (d_a,...
Recently, charge density wave (CDW) order in the CuO(2) planes of underdoped YBa(2)Cu(3)O(6+δ) was detected using resonant soft x-ray scattering. An important question remains: is chain layer responsible for this ordering? Here, we explore energy and polarization dependence scattering intensity a detwinned sample YBa(2)Cu(3)O(6.75) with ortho-III oxygen ordering layer. We show that CDW chains distinct from planes. The structure gives rise to commensurate superlattice reflection at Q=[0.33 0...
We report on a photo-induced transient state of YBa2Cu2O6+x in which transport perpendicular to the Cu-O planes becomes highly coherent. This effect is achieved by excitation with mid-infrared optical pulses, tuned resonant frequency apical oxygen vibrations, modulate both lattice and electronic properties. Below superconducting transition temperature Tc, equilibrium signatures interlayer coupling are enhanced. Most strikingly, induces new reflectivity edge at higher than Josephson plasma...
Abstract The excitonic insulator is a long conjectured correlated electron phase of narrow-gap semiconductors and semimetals, driven by weakly screened electron–hole interactions. Having been proposed more than 50 years ago, conclusive experimental evidence for its existence remains elusive. Ta 2 NiSe 5 semiconductor with small one-electron bandgap E G <50 meV. Below T C =326 K, putative stabilized. Here we report an optical excitation gap op ∼0.16 eV below comparable to the estimated...