Related papers: A 4-unit-cell superstructure in optimally doped YB…
We have investigated the electronic states in quasi one dimensional (1D) CuO chains by microprobe Angle Resolved Photoemission Spectroscopy. We find that the quasiparticle Fermi surface consists of six disconnected segments, consistent with…
We examine the effect of CuO intergrowths on the superconductivity in epitaxial La_{2/3}Ca_{1/3}MnO_3/YBa_2Cu_3O_{7-\delta} (LCMO/YBCO) thin-film heterostructures. Scanning transmission electron microscopy on bilayer LCMO/YBCO thin films…
A series of new Sr2-xBaxCuO3+y (0 x 0.6) superconductors were prepared using high-pressure and high-temperature synthesis. A Rietveld refinement based on powder x-ray diffraction confirms that the superconductors crystallize in the…
The competition of superconductivity and magnetism in superlattices composed of alternating YBa$_2$Cu$_3$O$_{7-d}$ and La$_{0.67}$Ca$_{0.33}$MnO$_{3}$ thin films is investigated using low-energy optical spectroscopy. The thickness of the…
The flurry of theoretical and experimental studies following the report of room-temperature superconductivity at ambient pressure in Cu-substituted lead apatite Cu$_x$Pb$_{10-x}$(PO$_4$)$_6$O (`LK99') have explored whether and how this…
Complex oxides are well known to develop oxygen ordering patterns with well defined periodicities, but their interplay with electronic correlations remains largely unexplored. Here, we report resonant and non-resonant x-ray diffraction data…
The YBa2Cu3O8-x and NaxWO3 superconductors are treated not as an ionic compounds but rather as an arrays of atoms featuring both covalent and metallic bonding. We accept as particle radii the positions of the principal maxima in the radial…
The superconducting transition temperature ($T_{\mathrm{c}}$) of trilayer or quadruple-layer cuprates typically surpasses that of single-layer or bilayer systems. This observation is often interpreted within the ``composite picture", where…
We have obtained isofield curves for the square root of the average kinetic energy density of the superconducting state for three single crystals of underdoped $YBa_2Cu_3O_{7-x}$, an optimally doped single crystal of…
Scanning tunneling spectroscopy (STS) studies reveal long-range spatial homogeneity and predominantly $d_{x^2-y^2}$-pairing spectral characteristics in under- and optimally doped $\rm YBa_2Cu_3O_{7-\delta}$ superconductors, whereas STS on…
The simplest cuprate superconductor La2CuO4+y with mobile oxygen interstitials exhibits a clear phase separation, but only recently a bulk multiscale structural phase separation has been observed by using scanning micro X-ray diffraction.…
Charge ordering in doped \cob planes near the commensurate fillings $x = {1/4}$ and 1/3 are considered for $Na_x CoO_2.yH_2O$ and suggested to be competitors to superconductivity, leading to the experimentally seen narrow superconducting…
For the recently discovered cuprate superconductor $\mathrm{Ba_{2}CuO_{3+\delta}}$, we propose a lattice structure which resembles the model considered by Lieb to represent the vastly oxygen-deficient material. We first investigate the…
We use resonant soft x-ray scattering (RSXS) to quantify the hole distribution in a superlattice of insulating La2CuO4 (LCO) and overdoped La_{2-x}Sr_{x}CuO4 (LSCO). Despite its non-superconducting constituents, this structure is…
A combination of neutron total scattering measurement and reverse Monte Carlo (RMC) refinement is applied to the study of apical Cu-O bond distortions in the high-Tc superconductor YBa2Cu3O6.93. We show that the average structure is not…
Superconductors are a striking example of a quantum phenomenon in which electrons move coherently over macroscopic distances without scattering. The high-temperature superconducting oxides(cuprates) are the most studied class of…
Recently, Matsukawa et al. have discovered a new superconductor Pr_2Ba_4Cu_7O_15-delta in which metallic CuO double chains are responsible for the superconductivity. To investigate the superconductivity, we employ the d-p double chain model…
The crystal structure and electrical resistivity of YBa$_2$Cu$_4$O$_8$ (Y124) were studied under high pressure up to 18 GPa using diamond-anvil cells, respectively, in order to clarify its conduction mechanism. Y124 causes the first-order…
Oxygen doping dimples the CuO_2 planes of YBa_2Cu_3O_{6.8-6.92} by displacing copper normal to the planes and further towards Ba. The correlated oxygen displacements, however, are constrained to the in-plane axes. This displacement pattern…
Recent scanning tunnelling spectroscopy (STS) experiments revealed remarkable role of a supercell consisting $4\times4$ CuO$_2$ unit cells in the emergence of local nematic state and preformed local Cooper pairs and phase coherent cuprate…