相关论文: Incommensurate spin-density wave order in electron…
In the metallic magnet NbFe2, the low temperature threshold of ferromagnetism can be investigated by varying the Fe concentration within a narrow homogeneity range. NbFe2 is one of a number of compounds where modulated order is found to…
We present neutron diffraction analysis of BaFe$_2$(As$_{1-x}$P$_x$)$_2$ over a wide temperature (10 to 300 K) and compositional ($0.11 \leq x \leq 0.79$) range, including the normal state, the magnetically ordered state, and the…
Elastic neutron scattering experiments showed incommensurate antiferromagnetic peaks in 5% Fe-substituted Bi-2201 cuprate in the non-superconducting heavily overdoped regime. The incommensurability delta~0.21 is comparable to that observed…
Neutron diffraction on a triple-axis spectrometer and a small-angle neutron scattering instrument is used to study the magnetic phase transition in tetragonal Ba$_2$CuGe$_2$O$_7$ at zero magnetic field. In addition to the incommensurate…
We have studied incommensurate spin ordering in single crystal underdoped La_{2-x}Ba_{x}CuO_{4} with x~0.08, 0.05 and 0.025 using neutron scattering techniques. Static incommensurate magnetic order is observed in the La_{2-x}Ba_{x}CuO_{4}…
We report an inelastic-neutron-scattering and muon-spin-relaxation study of the effect of 2% spinless (Zn) impurities on the magnetic order and dynamics of YBa$_2$Cu$_3$O$_{6.6}$, an underdoped high-temperature superconductor that exhibits…
In this Letter we report high-resolution synchrotron X-ray powder diffraction and transmission electron microscope analysis of Mn-substituted LaFeAsO samples, demonstrating that a static incommensurate modulated structure develops across…
A Neutron Powder Diffraction (NPD) experiment has been performed to investigate the structural phase transition and magnetic order in CaFe1-xCoxAsF superconductor compounds (x = 0, 0.06, 0.12). The parent compound CaFeAsF undergoes a…
We present the results of the first neutron powder and single crystal diffraction studies of the coupled spin tetrahedra systems ${\CuTeX}$ (X=Cl, Br). Incommensurate antiferromagnetic order with the propagation vectors…
It is shown that in the t-J model of Cu-O planes at low frequencies the dynamic spin structure factor is peaked at incommensurate wave vectors (1/2+-delta,1/2)$, (1/2,1/2+-delta). The incommensurability is connected with the momentum…
We report an investigation into the superconducting and magnetic properties of Fe_{1+y}Se_{x}Te_{1-x} single crystals by magnetic susceptibility, muon spin rotation, and neutron diffraction. We find three regimes of behavior in the phase…
We present an inelastic neutron scattering study on single-crystalline LiFeAs devoted to the characterization of the incommensurate antiferromagnetic fluctuations at $\mathbf{Q}=(0.5\pm\delta, 0.5\mp\delta, q_l)$. Time-of-flight…
We use magnetic long range order as a tool to probe the Cooper pair wave function in the iron arsenide superconductors. We show theoretically that antiferromagnetism and superconductivity can coexist in these materials only if Cooper pairs…
Inelastic neutron scattering measurements on Ba(Fe0.925Mn0.075)2As2 manifest spin fluctuations at two different wavevectors in the Fe square lattice, (1/2,0) and (1/2,1/2), corresponding to the expected stripe spin-density wave order and…
We investigate magnetic ordering in metallic Ba[Fe(1-x)Mn(x)](2)As(2) and discuss the unusual magnetic phase, which was recently discovered for Mn concentrations x > 10%. We argue that it can be understood as a Griffiths-type phase that…
SrCo2As2 is a peculiar itinerant magnetic system that does not order magnetically, but inelastic neutron scattering experiments observe the same stripe-type antiferromagnetic (AF) fluctuations found in many of the Fe-based superconductors…
We discuss the low energy theory of two-dimensional metals near the onset of spin density wave order. It is well known that such a metal has a superconducting instability induced by the formation of spin-singlet pairs of electrons, with the…
Using neutron scattering techniques, we have studied incommensurate spin ordering as well as low energy spin dynamics in single crystal underdoped \LBCO with x$\sim$0.095 and 0.08; high temperature superconductors with T$_C \sim$ 27 K and…
The compound EuFe(2-x)Co(x)As2 was investigated by means of the 57Fe and 151Eu Moessbauer spectroscopy versus temperature (4.2 - 300 K) for x=0 (parent), x=0.34 - 0.39 (superconductor) and x=0.58 (overdoped). It was found that spin density…
We report a doping dependent electronic Raman scattering measurements on iron-pnictide superconductor Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ single crystals. A strongly anisotropic gap is found at optimal doping for x=0.065 with $\Delta_{max}\sim…