Related papers: Antiferro--quadrupolar structures in UPd$_3$ infer…
The crystal structure of KAgF3 was studied by powder neutron diffraction. KAgF3 exhibits at all temperatures an orthorhombic symmetry in space group Pnma that allows for several distortions with respect to the ideal cubic perovskite…
Low-temperature, high-field (H[-110] <= 7.5 T), neutron diffraction experiments on single-crystal Ce0.70Pr0.30B6 are reported. Two successive incommensurate phases are found to exist in zero field. The appearance, for H >= 4.6 T at T = 2 K,…
X-ray scattering by multiferroic LuFe2O4 is reported. Below 320 K, superstructure reflections indicate an incommensurate charge order with propagation close to (1/3,1/3,3/2). The corresponding charge configuration, also found by electronic…
Hyperuniform point patterns can be classified by the hyperuniformity scaling exponent $\alpha > 0$, that characterizes the power-law scaling behavior of the structure factor $S(\mathbf{k})$ as a function of wavenumber $k\equiv|\mathbf{k}|$…
The enantiomorphous (chiral) crystal class of the Sohncke-type insulator Pb(TiO)Cu4(PO4)4 permits the rotation of the plane of polarization of light (optical activity). Copper ions participate in antiferromagnetic order below a temperature…
Previous x-ray diffraction studies have reported Eu to transform from the hcp structure to a new phase, Eu-III, at 18 GPa. Using x-ray powder diffraction we have determined that Eu remains hcp up to 33 GPa, and that the extra peaks that…
Using the QCD dipole picture of the BFKL pomeron, the gluon contribution to the cross-section for single diffractive dissociation in deep-inelastic high-energy scattering is calculated. The resulting contribution to the proton diffractive…
We present single-crystal neutron diffraction measurements on multiferroic LuFe2O4 showing phase transitions at 240 and 175 K. Magnetic reflections are observed below each transition indicating that the magnetic interactions in LuFe2O4 are…
Neutron elastic and inelastic scattering measurements have been performed in order to investigate the spin structure and the magnetic excitations in the impurity-induced antiferromagnetic ordered phase of the doped spin gap system…
Through powder x-ray diffraction we have investigated the structural behavior of SmVO3, in which orbital and magnetic degrees of freedom are believed to be closely coupled to the crystal lattice. We have found, contrary to previous reports,…
We examine trends in the wavevectors and form-factors of charge density wave instabilities of three-band models of the underdoped cuprates. For instabilities from a high temperature state with a large Fermi surface, we extend a study by…
The Bragg regime shifts when conventional materials in a multilayer distributed Bragg reflector (DBR) are replaced by artificial materials with the so-called negative index of refraction. This provides an avenue for characterizing the…
We report experimental evidence for pressure instabilities in the model multiferroic BiFeO3 and namely reveal two structural phase transitions around 3 GPa and 10 GPa by using diffraction and far-infrared spectroscopy at a synchrotron…
Ba(Fe$_{1/2}$Nb$_{1/2}$)O$_3$ (BFN) ceramics are considered to be promising for technological applications owing to their high dielectric constant over a wide range of temperatures. However, there exists considerable discrepancy over the…
The Pockels effect can increase the effective birefringence of ambichiral, electro--optic rejection filters made of materials with a $\bar{4}2m$ point group symmetry, when a dc electric field is applied parallel to the axis of…
We have performed elastic and inelastic neutron scattering experiments on the solid solutions U(Ru_{1-x}Rh_x)_2Si_2 for the Ru rich concentrations: x=0, 0.01, 0.02, 0.025, 0.03, 0.04 and 0.05. Hidden order is suppressed with increasing x,…
We report on the ultrafast dynamics of charge order and structural response during the photoinduced suppression of charge and orbital order in a mixed-valence manganite. Employing femtosecond time-resolved resonant x-ray diffraction below…
The superstructure spots that appear in diffraction patterns of tilted perovskites are well documented and easily calculated using crystallographic software. Here, by considering a distortion mode as a perturbation of the prototype…
The photonic band dispersion and density of states (DOS) are calculated for the three-dimensional (3D) hexagonal structure corresponding to a distributed Bragg reflector patterned with a 2D triangular lattice of circular holes. Results for…
We have investigated the low temperature phase of a Nd0.5Sr0.5MnO3 single crystal by x-ray resonant scattering at the Mn K-edge of the (3 0 0), (0 3 0) and (0 5/2 0) reflections. Strong resonances were observed for the s-s' channel in the…