Nematicity and Charge Order in Superoxygenated La_{2-x}Sr_{x}CuO_{4+y}.

In this Letter, we report a resonant x-ray scattering measurement of stripelike charge order in the 1/8th doped component of electronically phase-separated, orthorhombic La_{2}CuO_{4+y}. This observation is coupled to the absence of any resonant (001) peak, which at different resonant energies has been identified with the presence of low-temperature-tetragonal-like structural tilt patterns or nematicity in the CuO planes. Thus, we provide evidence that structural pinning is not necessary for the formation of static charge stripes and that the relationship between charge nematicity and stripes may not be simple.

Correction: Origin of the temperature dependence of the energy gap in Cr-doped BiSe.

Correction for 'Origin of the temperature dependence of the energy gap in Cr-doped Bi2Se3' by Turgut Yilmaz et al., Phys. Chem.

Origin of the temperature dependence of the energy gap in Cr-doped BiSe.

Recent progress in impurity-doped topological insulators has shown that the gap at the Dirac point shrinks with reducing temperature. This is an obstacle for experimental realization of the quantum anomalous Hall effect at higher temperature due to the requirement of a larger energy gap. In order to solve this puzzle, we study the gap at the Dirac point by performing temperature-dependent photoemission spectroscopy and X-ray diffraction experiments in Cr-doped Bi2Se3.

Application of glancing-emergent-angle fluorescence for polarized XAFS studies of single crystals.

X-ray absorption fine-structure (XAFS) data were obtained for the V K-edge for a series of anisotropic single crystals of (Cr(x)V(1-x))(2)O(3). The data and the results were compared for the as-prepared bulk single crystals (measured in fluorescence in two different orientations) and those ground to powder (measured in transmission). For the bulk single crystals, the glancing-emergent-angle (GEA) method was used to minimize fluorescence distortion.

Strain-induced bond buckling and its role in insulating properties of Cr-doped V2O3.

Structural transformations around both V and Cr atoms in (V1-xCrx)2O3 across its metal-insulator transition (MIT) at x approximately 0.01 are studied by extended x-ray absorption fine-structure technique. Our new results for Cr made possible by the use of a novel x-ray analyzer that we developed reveal the substitutional mechanism of Cr doping.

Phase separation in superoxygenated La2-xSrxCuO4+y.

The complex interplay between superconducting and magnetic phases remains poorly understood. Here, we report on the phase separation of doped holes into separate magnetic and superconducting regions in superoxygenated La(2-x)Sr(x)CuO(4+y), with various Sr contents. Irrespective of Sr-doping, excess oxygen raises the superconducting onset to 40 K with a coexisting magnetic spin-density wave that also orders near 40 K in each of our samples.

A magnetic route to measure the average oxidation state of mixed-valent manganese in manganese oxide octahedral molecular sieves (OMS).

A magnetic route has been applied for measurement of the average oxidation state (AOS) of mixed-valent manganese in manganese oxide octahedral molecular sieves (OMS). The method gives AOS measurement results in good agreement with titration methods. A maximum analysis deviation error of +/-7% is obtained from 10 sample measurements.

Extension of a tuned log spiral of revolution fluorescence XAFS detector, designed for optimal detection of a particular element Z, to XAFS of elements other than Z.

Recently, it has been demonstrated that an x-ray detector in the form of a log spiral of revolution, covered with highly oriented pyrolytic graphite, is an excellent device for obtaining the fluorescence XAFS of an element of interest in the presence of competing fluorescence from other elements. In the present work we investigate the capabilities of a log spiral of revolution (LSR) detector, with a geometry optimized for one element (in this case Cr), if used for XAFS of other elements.

Method of linearizing the 3d L3/L2 white line ratio as a function of magnetic moment.

We have developed a parameterization method which linearizes the relationship between local magnetic moment and the 3d L3/L2 "white line" ratio as observed in electron energy loss spectroscopy or X-ray near edge absorption spectroscopy. We first establish that the parameterization linearizes an existing theoretical result for ratio versus moment. We then test our method on data sets for which a white line ratio has been previously published by other authors, who have studied a series of compounds using a consistent deconvolution procedure.