相关论文: Magnetic Resonant Mode in the Single-Layer High Te…
We use neutron scattering to study magnetic excitations near the antiferromagnetic wave vector in the underdoped single-layer cuprate HgBa2CuO4+{\delta} (superconducting transition temperature Tc ~ 88 K, pseudogap temperature T* ~ 220 K).…
Inelastic neutron scattering was used to study the wavevector- and frequency-dependent magnetic fluctuations in single crystals of superconducting YBa$_2$Cu$_3$O$_{6+x}$. The spectra contain several important features, including a gap in…
High-temperature (high-Tc) superconductivity in the copper oxides arises from electron or hole doping of their antiferromagnetic (AF) insulating parent compounds. The evolution of the AF phase with doping and its spatial coexistence with…
Superconductivity appears to compete against the spin-density-wave in Fe pnictides. However, optimally cobalt doped samples show a quasi-two-dimensional spin excitation centered at the (0.5, 0.5, L) wavevector, "the spin resonance peak",…
An inelastic neutron scattering experiment has been performed in the high-temperature superconductor $\rm YBa_2Cu_3O_{6.89}$ to search for an oxygen-isotope shift of the well-known magnetic resonance mode at 41 meV. Contrary to a recent…
Spin excitations are one of the top candidates for mediating electron pairing in unconventional superconductors. Their coupling to superconductivity is evident in a large number of systems, by the observation of an abrupt redistribution of…
The fundamental mechanism that gives rise to high-transition-temperature (high-Tc) superconductivity in the copper oxide materials has been debated since the discovery of the phenomenon. Recent work has focussed on a sharp 'kink' in the…
A notable aspect of high-temperature superconductivity in the copper oxides is the unconventional nature of the underlying paired-electron states. The appearance of a resonance peak, observed in inelastic neutron spectroscopy in the…
Neutron scattering experiments reveal that a diagonal spin modulation, which is a one-dimensional modulation rotated away by 45$^\circ$ from that in the superconducting phase, occurs universally across the insulating spin-glass phase in…
Resonant magnetic modes with odd and even symmetries were studied by inelastic neutron scattering experiments in the bilayer high-$T_c$ superconductor $\rm Y_{1-x}Ca_{x}Ba_2Cu_3O_{6+y}$ over a wide doping range. The threshold of the spin…
The fundamental building block of the copper oxide superconductors is a Cu4O4 square plaquette. In most of these materials, the plaquettes are slightly distorted and form a rectangular lattice. An influential theory predicts that…
The universal behaviour of the magnetic excitations in high-temperature superconductors is described in a model with static stripes retaining only the localized spin degrees of freedom. The stripes are represented by a model of coupled…
A high temperature electrochemical oxidation process has been used to produce large single crystals of $La_2CuO_{4 + \delta}$ suitable for neutron scattering experiments. Below room temperature the oxygen-rich phases have structural…
Spin excitations in the overdoped high temperature superconductors Tl$_2$Ba$_2$CuO$_{6+\delta}$ and (Bi,Pb)$_2$(Sr,La)$_{2}$CuO$_{6+\delta}$ were investigated by resonant inelastic x-ray scattering (RIXS) as functions of doping and detuning…
Neutron scattering has been used to study the spin fluctuations in the YBa$_2$Cu$_3$O$_{7-x}$ and Bi$_2$Sr$_2$CaCu$_2$O$_8$ materials. Evidence is found for both incommensurate fluctuations and a commensurate resonance excitation.…
We report neutron scattering measurements of spin density wave order within the superconducting state of a single crystal of predominately stage-4 La2CuO4+y with a Tc(onset) of 42 K. The low temperature elastic magnetic scattering is…
The coupling of spin, charge and lattice degrees of freedom results in the emergence of novel states of matter across many classes of strongly correlated electron materials. A model example is unconventional superconductivity, which is…
Within the t-J model of copper-oxides, the condensation energy can be related to the change in the dynamical spin structure factor between the superconducting and the normal states. By analyzing previous experimental data, we show that the…
The quantum spin fluctuations of the S = 1/2 Cu ions are important in determining the physical properties of the high-transition temperature (high-Tc) copper oxide superconductors, but their possible role in the electron pairing for…
We have used inelastic neutron scattering to examine the magnetic fluctuations at intermediate frequencies in the simplest high temperature superconductor, La_{2-x}Sr_{x}Cu_{4}. The suppression of the low energy magnetic response in the…