相关论文: Spin Fluctuations in Sr$_{1.8}$La$_{0.2}$RuO$_4$

We use inelastic neutron scattering to study spin excitation anisotropy in mechanically detwinned Ba(Fe1-xCox)2As2 with x = 0.048 and 0.054. Both samples exhibit a tetragonal-to-orthorhombic structural transition at Ts, a collinear static…

Motivated by recent angle-resolved photoemission spectroscopy (ARPES) experiments, we analyze the temperature, frequency, and momentum dependence of the single-particle scattering rate in a model of the $\gamma$-band of Sr$_2$RuO$_4$ under…

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…

The spin susceptibility of strongly correlated Sr$_2$RuO$_4$ is known to display a rich structure in reciprocal space, with a prominent peak at ${\bf Q}_i$=$(0.3,0.3,0)$. It is still debated if the resulting incommensurate spin-density-wave…

We propose a quantitative model for triplet superconductivity in Sr_2RuO_4 based on first principles calculations for the electronic structure and magnetic susceptibility. The superconductivity is due to ferromagnetic spin fluctuations,…

A neutron scattering study of heavily hole-overdoped superconducting KFe$_2$As$_2$ revealed a well-defined low-energy incommensurate spin fluctuation at [$\pi(1\pm2\delta$),0] with $\delta$ = 0.16. The incommensurate structure differs from…

Using a two-dimensional Hubbard Hamiltonian for the three electronic bands crossing the Fermi level in Sr$_2$RuO$_4$ we calculate the band structure and spin susceptibility $\chi({\bf q}, \omega)$ in quantitative agreement with nuclear…

A small number of superconductors are believed to exhibit intrinsic spin triplet pairing, and they are often discussed in terms of a simple, $^3$He-like picture where ferromagnetic spin fluctuations provide the "glue". However, in some…

We have investigated the spin fluctuations at energy transfers up to ~110 meV, well above the resonance energy (33 meV) in the YBa2Cu3O6.5 ortho-II superconductor using neutron time-of-flight and triple-axis techniques. The spectrum at high…

Using a three-band Hubbard Hamiltonian we calculate within the random-phase-approximation the spin susceptibility, $\chi({\bf q},\omega)$, and NMR spin-lattice relaxation rate, 1/T$_1$, in the normal state of the triplet superconductor…

Neutron scattering has been used to study the structure and spin dynamics of La$_{0.85}$Sr$_{0.15}$MnO$_3$. The magnetic structure of this system is ferromagnetic below T_C = 235 K. We see anomalies in the Bragg peak intensities and new…

Recently a debate has arisen over which of the two distinct parts of the Fermi surface of Sr2RuO4, is the active part for the chiral p-wave superconductivity. Early theories proposed p-wave pairing on the two dimensional gamma-band, while a…

A comprehensive inelastic neutron scattering study of magnetic excitations in the near-optimally doped high-temperature superconductor ${\rm YBa_{2}Cu_{3}O_{6.85}}$ is presented. The spin correlations in the normal state are commensurate…

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 provide results for the leading superconducting instabilities for a model pertaining to Sr$_2$RuO$_4$ obtained within spin-fluctuation mediated superconductivity in the very weak-coupling limit. The theory incorporates spin-orbit…

As additional neutron scattering experiments are performed on a variety of high temperature superconducting compounds it appears that magnetic incommensuration is a phenomenon common to all of the samples studied. The newest experimental…

Low energy spin fluctuations are studied for the electron-doped Fe-based superconductor LaFeAsO(1-x)F(x) by inelastic neutron scattering up to the energy transfer of w = 15 meV using polycrystalline samples. Superconducting samples…

Neutron scattering is used to probe magnetic excitations in FeSe_{0.4}Te_{0.6} (T_c=14 K). Low energy spin fluctuations are found with a characteristic wave vector $(0.5,0.5,L)$ that corresponds to Fermi surface nesting and differs from…

Inelastic neutron scattering is used to study the magnetic excitations of the $S=1$ square-lattice antiferromagnet La$_2$NiO$_4$. We find that the spin waves cannot be described by a simple classical (harmonic) Heisenberg model with only…

Van Hove singularities (VHss) in the vicinity of the Fermi energy often play a dramatic role in the physics of strongly correlated electron materials. The divergence of the density of states generated by VHss can trigger the emergence of…