Related papers: NMR study on the local structure in La-based high-…
The structure of a new member of the AxCoO2 x nH2O family (A=Li,Na,K) was determined by high-resolution synchrotron X-ray powder diffraction. Layered lithium cobalt oxide hydrate LixCoO2 x 2H2O crystallizes in a disordered monoclinic…
Nuclear quadrupole resonance (NQR) on copper nuclei has been applied for studies of the electronic properties of quasi-two-dimensional low-temperature superconductor CuS (covellite) in the temperature region between 1.47 and 290 K. Two NQR…
Recent experiments in the original cuprate high temperature superconductor, La$_2-x$Ba$_x$CuO$_4$, have revealed a remarkable sequence of transitions [1]. Here we investigate such crystals with Kerr effect which is sensitive to…
The quasi-2D Pt-based rare earth intermetallic material LaPt$_2$Si$_2$ has attracted attention as it exhibits strong interplay between charge density wave (CDW) and and superconductivity (SC). However, the most of the results reported on…
Superconductivity, at 2-3 K, was observed in a novel phase of the ternary Li-Rh-B system. The structural phase exhibits a large noncentrosymmetric cubic unit cell with the a-parameter being within 1.208 \leq a \leq 1.215 nm. This phase is…
In crystals of La2CuO4.02 oxygen diffusion can be limited to such small length scales, that the resulting phase separation is invisible for neutrons. Decomposition of the 139La NQR spectra shows the existence of three different regions, of…
We report $^{139}$La and $^{63}$Cu nuclear magnetic and quadrupole resonance (NMR/NQR) studies in an underdoped La$_{1.93}$Sr$_{0.07}$CuO$_4$ single crystal, focusing on the $^{139}$La NMR in the normal state. We demonstrate that the local…
Several recent experiments have revealed that the charge density $\rho$ in a given compound (mostly underdoped) is intrinsic inhomogeneous with large nanoscale spatial variations. Therefore it is appropriate to define a local charge density…
The experimental observations of stripes in superconducting cuprates and insulating nickelates clearly show the modulation in charge and spin density. However, these have proven to be rather insensitive to the harmonic structure and (site…
Granular superconductivity occurs when microscopic superconducting grains are separated by non-superconducting regions through which they communicate by Josephson tunneling to establish the macroscopic superconducting state [1]. Although…
Superlattices of the repeated structure La(1.56)Sr(0.44)CuO(4)/La(2)CuO(4) (LSCO-LCO), where none of the constituents is superconducting, show a superconducting transition of T_c \simeq 25 K. In order to elucidate the nature of the…
In a recent paper [arXiv:0804.3569], Takatoshi Nomura {\it et al.} reported a structural phase transition near 150 K in LaOFeAs and used space group "Cmma" to describe their X-ray diffraction data. However, they did not discuss how their…
The low-temperature (LT) superstructure of $\alpha'$-NaV$_2$O$_5$ was determined by synchrotron radiation x-ray diffraction. Below the phase transition temperature associated with atomic displacement and charge ordering at 34K, we observed…
We report on the phase diagram for charge-stripe order in La(1.6-x)Nd(0.4)Sr(x)CuO(4), determined by neutron and x-ray scattering studies and resistivity measurements. From an analysis of the in-plane resistivity motivated by recent…
We have investigated low-temperature crystal structure of BiCh2-based compounds LaO1-xFxBiSSe (x = 0, 0.01, 0.02, 0.03, and 0.5), in which anomalous two-fold-symmetric in-plane anisotropy of superconducting states has been observed for x =…
We report inelastic neutron scattering on single crystals of the bilayer cuprate family La$_{2-x}$Ca$_{1+x}$Cu$_{2}$O$_{6+\delta}$, including two crystals made superconducting (transitions at 45 and 55 K) by high-pressure annealing in an…
We performed magnetic inelastic neutron-scattering experiments on La(1.93)Sr(0.07)CuO(4) over a wide range of E and T;2 < E < 44 meV and 1.5 < T < 300 K. The dynamic susceptibility X"(q,E) of this underdoped high-Tc superconductor (Tc = 17…
High-temperature superconductivity has been discovered in La2-xBaxCuO4 [1], a compound that derives from the undoped La2CuO4 crystallizing in the perovskite T-structure. In this structure oxygen octahedra surround the copper ions. It is…
High-transition-temperature (high-T_c) superconductivity in cuprates has been discovered for more than three decades, but the underlying mechanism remains a mystery. Cuprates are the only unconventional superconducting family that host bulk…
We present a diffuse neutron and x-ray scattering study of structural, spin- and charge-density-wave fluctuations in the electrical insulator La$_{2-x}$Sr$_x$NiO$_4$. This lamellar nickelate is an isostructural analogue of the…