Javier Herrero-Martín

Design and performance of BOREAS, the beamline for resonant X-ray absorption and scattering experiments at the ALBA synchrotron light source

The optical design of the BOREAS beamline operating at the ALBA synchrotron radiation facility is described. BOREAS is dedicated to resonant X-ray absorption and scattering experiments using soft X-rays, in an unusually extended photon energy range from 80 to above 4000 eV, and with full polarization control. Its optical scheme includes a fixed-included-angle, variable-line-spacing grating monochromator and a pair of refocusing mirrors, equipped with benders, in a Kirkpatrick-Baez arrangement. It is equipped with two end-stations, one for X-ray magnetic circular dichroism and the other for resonant magnetic scattering. The commissioning results show that the expected beamline performance is achieved both in terms of energy resolution and of photon flux at the sample position.

Magnetic frustration, phase competition, and the magnetoelectric effect in NdFe3(BO3)4.

We present an element selective resonant magnetic x-ray scattering study of NdFe3(BO3)4 as a function of temperature and applied magnetic field. Our measurements show that the magnetic order of the Nd sublattice is induced by the Fe spin order. When a magnetic field is applied parallel to the hexagonal basal plane, the helicoidal spin order is suppressed and a collinear ordering, where the moments are forced to align in a direction perpendicular to the applied magnetic field, is stabilized. This result excludes a noncollinear spin order as the origin of the magnetically induced electric polarization in this compound. Instead our data imply that magnetic frustration results in a phase competition, which is the origin of the magnetoelectric response.

Hard x-ray probe to study doping-dependent electron redistribution and strong covalency in La1−xSr1+xMnO4

The doping dependence of the occupied

On the correlation between the X-ray absorption chemical shift and the formal valence state in mixed-valence manganites

3d

Magnetic anisotropy and valence states in La2Co1−xMn1+xO6 ( x≈0.23 ) thin films studied by x-ray absorption spectroscopy techniques

states at the Mn sites of

Resonant x-ray scattering in 3d-transition-metal oxides: Anisotropy and charge orderings

{\text{La}}_{1\ensuremath{-}x}{\text{Sr}}_{1+x}{\text{MnO}}_{4}

Magnetic stability against calcining of microwave-synthesized CoFe2O4 nanoparticles

(

Structural, electrical and magnetic properties of RE1/3Sr2/3FeO3 compounds (RE = La, Pr, Nd, Eu and Gd)

x=0

Magnetostructural coupling, magnetic ordering, and cobalt spin reorientation in metallic P r0.5 S r0.5Co O3 cobaltite

, 0.3, and 0.5) was studied by means of nonresonant hard x-ray emission spectroscopy. For the single-crystalline samples, we observe a linear dichroism of the

Control of coexisting magnetic phases by electric fields in NdFe 3 ( BO 3 ) 4

\text{Mn}\text{ }K\ensuremath{\beta}