Related papers: Phonon anomalies with doping in superconducting ox…

Using ultrafast optical techniques, we detect two types of bosons strongly coupled to electrons in the family of Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ from the underdoped to overdoped regimes. The different doping dependences of the…

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…

We report inelastic neutron scattering measurements of the phonon density-of-states in superconducting Sr0.6K0.4Fe2As2 (Tc=30 K) and Ca0.6Na0.4Fe2As2 (Tc=18 K). Compared with the parent compound BaFe2As2 doping affects mainly the lower and…

A systematic Raman study in the visible carried out on the YBa2Cu316,18Ox (x=6-7) compounds, with isotopic substitution of 18O for 16O, has detected a doping dependent deviation from harmonic behavior for the frequency shift of the in-phase…

Here we study the effect of Ca doping on charge transfer mechanism of polycrystalline YBa2Cu3O7-{\delta} compound. The samples of composition Y1-xCaxBa2Cu3O7-{\delta} (x = 0.00, 0.05, 0.10, 0.20 and 0.30) are synthesized through standard…

We report results of inelastic neutron scattering measurements of phonon dispersions in optimally doped YBa2Cu3O6.95 and compare them with model calculations. The focus is on the in-plane oxygen bond-stretching phonon branches. The study of…

We present a detailed temperature-dependent Raman light scattering study of optical phonons in molecular-beam-epitaxy-grown films of the electron-doped superconductor La_{2-x}Ce_{x}CuO_{4} close to optimal doping (x ~ 0.08, T_c = 29 K and x…

We report the first measurement of the optical phonon dispersion in optimally doped single layer Bi2Sr1.6La0.4Cu2O6+delta using inelastic x-ray scattering. We found a strong softening of the Cu-O bond stretching phonon at about q=(0.25,0,0)…

Using Resonant Inelastic X-ray Scattering, we measure the paramagnon dispersion and damping of undoped, antiferromagnetic Ca$_2$CuO$_2$Cl$_2$ as well as doped, superconducting Na$_{x}$Ca$_{2-x}$CuO$_2$Cl$_2$. Our estimation of the…

Critical behavior of the infrared reflectivity of RuSr_2GdCu_2O_8 ceramics is observed near the superconducting T_{SC} = 45 K and magnetic T_M = 133 K transition temperatures. The optical conductivity reveals the typical features of the…

We explain the anomalous doping dependence of zone boundary $(\pi,0)$ and $(\pi,\pi)$ bond-stretching phonons in the high-temperature superconductor La$_{2-\delta}$Sr$_{\delta}$CuO$_4$ in the doping range $0<\delta<0.35$. Our calculations…

We report systematic studies of structural, microstructural and transport properties of Y1-xCaxBa2Cu3O7-d bulk samples with 0.20 x 0.0. The partial substitution of Ca2+ at Y3+ site in YBa2Cu3O7-d leads towards slightly overdoped regime,…

The lattice dynamics of Ba1-xKxFe2As2 (x = 0.00, 0.27) have been studied by inelastic X-ray scattering measurement at room temperature. K doping induces the softening and broadening of phonon modes in the energy range E = 10-15 meV.…

We investigate in the framework of linear response theory the complete phonon dispersion, phonon induced electronic charge response, electron-phonon interaction and dielectric and infrared properties of the high-temperature superconductors…

Bulk n-type SrTiO3 (STO) has long been known to possess a superconducting ground state at an exceptionally dilute carrier density. This has raised questions about the applicability of the BCS-Eliashberg paradigm with its underlying…

We investigate the hole and lattice dynamics in a prototypical high temperature superconducting system La{2-x}Sr{x}CuO{4} using infrared spectroscopy. By exploring the anisotropy in the electronic response of CuO2 planes we show that our…

We report the structural, superconducting, magnetic and granular properties of Y1-xCaxBa2Cu3O7; x = 0.0, 0.1, 0.2 and 0.3. Rietveld fitted X-ray diffraction data confirms the single phase formation for all the samples. The orthorhombicity…

We report a comparative study of the dynamics of Cu2O, Ag2O and Au2O (i.e. M2O with M = Au, Ag and Cu) using first principle calculations based on the density functional theory. Here for the first time we show that the nature of chemical…

Using the density-functional perturbation theory with structural optimization, we investigate the electronic structure, phonon spectra, and superconductivity of BiS2-based layered compounds LaO1-xFxBiS2. For LaO0.5F0.5BiS2, the calculated…

Temperature and composition dependences of high-energy longitudinal optical (LO) phonons in YBa2Cu3O{6+x}, studied by inelastic neutron scattering measurements, provide clear evidence for temperature dependent spatial inhomogeneity of doped…