相关论文: Charge localization and phonon spectra in hole dop…

Inelastic neutron scattering has been used to study the in-plane Cu-O bond-stretching mode in oxygen doped La$_{1.94}$Sr$_{0.06}$CuO$_{4.035}$ ($T_c = 38\,\text{K}$) and La$_2$CuO$_{4+\delta}$ ($T_c = 43\,\text{K}$). Similar to results from…

We present local structural evidence supporting the presence of charge inhomogeneities in the CuO2 planes of underdoped La2-xSrxCuO4. High-resolution atomic pair distribution functions have been obtained from neutron powder diffraction data…

For La_(1 2/3)Sr_(1/3)NiO_4 -- a commensurately doped Mott-Hubbard system -- charge- and spin-ordering in a stripe phase has been investigated by phononic and magnetic Raman scattering. Formation of a superlattice and an opening of a…

We performed a resonant inelastic X-ray scattering (RIXS) study of La$_{2-x}$Sr$_{x}$NiO$_{4+{\delta}}$ (LSNO) at the oxygen $K$ edge to investigate the nature of the doped holes with regard to charge excitations. Charge excitations of the…

The phonon densities-of-states of La(1.475)Nd(0.4)Sr(0.125)CuO(4) and La(1.9)Sr(0.1)CuO(4) were measured using inelastic neutron scattering. The ~70 meV phonon band which appears due to hole doping in La(1.9)Sr(0.1)CuO(4) is known to arise…

Stripe phases were predicted to arise in doped antiferromagnets through competition between magnetism and the kinetic energy of mobile carriers (typically holes). In copper-oxides the main experimental evidence for stripes is neutron…

The insulator-to-metal transition continues to be a challenging subject, especially when electronic correlations are strong. In layered compounds, such as La2-xSrxNiO4 and La2-xBaxCuO4, the doped charge carriers can segregate into…

Strong resonant enhancements of the charge-order and spin-order superstructure-diffraction intensities in La1.8Sr0.2NiO4 are observed when x-ray energies in the vicinity of the Ni L2,3 absorption edges are used. The pronounced photon-energy…

The lattice dynamics in Sr$_2$RuO$_4$ has been studied by inelastic neutron scattering combined with shell-model calculations. The in-plane bond-stretching modes in Sr$_2$RuO$_4$ exhibit a normal dispersion in contrast to all electronically…

Inelastic neutron scattering was used to study the Cu-O bond-stretching vibrations in optimally doped La1.85Sr0.15CuO4 (Tc = 35 K) and in two other cuprates showing static stripe order at low temperatures, i.e. La1.48Nd0.4Sr0.12CuO4 and…

Phononic and magnetic Raman scattering are studied in La$_{2-x-y}$Nd$_{y}$Sr$_{x}$CuO$_{4}$ with three doping concentrations: x ~ 1/8, y = 0; x ~ 1/8, y = 0.4; and x = 0.01, y = 0. We observe strong disorder in the tilt pattern of the…

Using first-principles density functional theory calculations, we investigated the effect of charge doping in a LaNiO$_3$/SrTiO$_3$ superlattice. The detailed analysis based on two different simulation methods for doping clearly shows that…

The high-energy phonons in La1.5Sr0.5NiO4, in which the checkerboard charge ordering is formed, was investigated by the inelastic neutron scattering. We found that the longitudinal modes show strong anomalies compared with La2NiO4. We argue…

We report a detailed neutron scattering study of the ordering of spins and holes in oxygen-doped La(2)NiO(4.133). The single-crystal sample exhibits the same oxygen-interstitial order but better defined charge-stripe order than that studied…

We report a neutron scattering study of bond-stretching phonons in La(1.69)Sr(0.31)NiO(4), a doped antiferromagnet in which the added holes order in diagonal stripes at 45 deg to the Ni-O bonds. For the highest-energy longitudinal optical…

Resonant soft X-ray scattering with photon energies near the O K and the Cu L3 edges was used to study charge ordering in the system La_{1.8-x}Eu_{0.2}Sr_xCuO_4 as a function of temperature for x = 0.125 and 0.15. From the superstructure…

By considering both the average structural parameters obtained from Rietveld refinement of neutron powder diffraction data, and the local structural parameters obtained from the atomic pair distribution function, we have tested the recent…

We study nickelate-centered and oxygen-centered stripe phases in doped La$_{2}$NiO$_{4}$ materials. We use an inhomogeneous Hartree-Fock and random-phase approximation approach including both electron-electron and electron-lattice(e-l)…

Using resonant X-ray diffraction and Raman spectroscopy, we study charge correlations and lattice dynamics in two model cuprates, HgBa$_{2}$CuO$_{4+\delta}$ and HgBa$_{2}$CaCu$_{2}$O$_{6+\delta}$. We observe a maximum of the characteristic…

We investigate electronic excitations in La2-x(Br,Sr)xCuO4 using resonant inelastic x-ray scattering (RIXS) at the oxygen K edge. RIXS spectra of the hole-doped cuprates show clear momentum dependence below 1 eV. The spectral weight…