LAMURA , G.

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 the low-temperature orthorhombic phase, whose modulation wave vector depends on the Mn content. The...

Electric and thermoelectric transport properties are mutually intertangled in diffusive transport equations. In particular, in high mobility multiband systems an anomalous behavior may occur, which can be tracked down to the properties of the individual bands. Here, we present magnetoelectric and magnetothermoelectric transport properties of a...

The crystal structure of the new ternary ThNi6Si6 and UNi6Si6 intermetallic compounds has been investigated by means of both single crystal and powder X-ray diffraction followed by Rietveld refinement. Both compounds adopt the tetragonal CeNi6Si6-type structure, crystallizing in the space group P4/nbm (No. 125) (Pearson's symbol tP52). This...

The local structure of La(Fe1-xMnx)AsO, showing suppression of long-range magnetic order by Mn-substitution, has been studied. Extended X-ray absorption fine structure (EXAFS) measurements at As K-edge and Fe K-edge are used to probe the atomic correlations in the FeAs-layer. We have found that both Fe-As and Fe-Fe bondlengths tend to increase...

Eu2In and Eu2Sn crystallize in the orthorhombic Co2Si-type structure (oP12, Pnma, No. 62) with In and Sn atoms occupying one 4c site and the Eu atoms filling two other 4c sites. Eu2In has a nearly ideal first-order magnetostructural transition (FOMT) at 55 K with a hysteresis of less than 0.1 K, a large entropy change and an adiabatic...

The study of overdoped FeTe1-xSex (0.5 < x < 1) polycrystalline superconductor samples is reported. The samples were prepared using a melting technique previously developed by our group. Increasing the Se content a phase separation related to the formation of FeSe inside the Fe(Se,Te) phase happens, as demonstrated by structural analysis and...

Nitroxides have great potential as contrast agents for Magnetic Resonance Imaging (MRI). Two b - cyclodextrin ( b CD) derivatives bearing one or seven (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) units on the small rim of b CD (CD3 and CD6 respectively) were synthesized. Their e ff ective magnetic moments were...

In the heavy-fermion system Yb2Pd2In1-xSnx, the interplay of crystal-field splitting, Kondo effect, and Ruderman-Kittel-Kasuya-Yosida interactions leads to complex chemical-, pressure-, and magnetic-field phase diagrams still to be explored in full detail. By using a series of techniques, we show that even modest changes of parameters other...

The deliberate insertion of magnetic Mn dopants in the Fe sites of the optimally doped SmFeAsO0.88F0.12 iron-based superconductor can modify in a controlled way its electronic properties. The resulting phase diagram was investigated across a wide range of manganese contents (x) by means of muon-spin spectroscopy (μSR), both in zero and in...