[en] The Basic Energy Sciences Synchrotron Radiation Center Collaborative Access Team (BESSRC-CAT) has built a bending magnet beamline for spectroscopy and scattering experiments at the Advanced Photon Source (APS). The windowless beamline uses a water cooled, double crystal, fixed exit monochromator with Si 1 1 1 crystals as the first optical element. The monochromator is capable of operations from 55 degree sign to 3 degree sign allowing experiments from approximately 2.5-30 keV. A monochromatic double mirror system located in the white-beam enclosure focuses the beam in the experimental station. When the first mirror is removed energies above the mirror cutoff (∼22 keV) can be used. The 12BM-B user station is equipped for scattering (Huber 6-circle diffractometer) and spectroscopy (optical table, ion chambers and solid state detectors) experiments

[en] The elliptical multipole wiggler located at Sector 11 of the Advanced Photon Source has a maximum critical energy of 32 keV and a total power output of ∼ 8 kW. The device produces circularly polarized X-rays on-axis and linearly polarized X-rays above and below the ring plane. A double crystal monochromator intercepts the lower linearly polarized radiation to be used in the 11ID-D experimental station for scattering and spectroscopy experiments in the 5 to 40 keV energy range. The on-axis circularly polarized photons and upper linearly polarized photons are monochromatized by one crystal horizontally deflecting monochromators at fixed Bragg angles of θ = 3.8 deg. and θ = 1.9 deg. respectively. We will present here the designs and detail the performance of Laue and Bragg monochromator designs for these two beamlines which operate at fixed energies from ∼60 keV to 125 keV. For the high-energy diffraction station, 11ID-C, which utilizes the upper linearly polarized radiation, the Laue monochromator design allows rapid interchange of crystals and provides a photon flux of 2 x 1012 photons/sec in a 2.5 x 3.5 mm spot at 98 keV using annealed Silicon crystals (Si(220)). The Bragg monochromator design provides focusing and a smaller bandwidth while retaining a high photon flux. The high heatloads generated by the EMPW present design challenges for both monochromator designs

[en] 25 nm thick Gd-doped ceria thin films were grown on yttria-stabilized zirconia (YSZ) substrates with (110) and (111) orientation by pulsed laser deposition to study both their crystalline structure and interfacial stability. The films were characterized by high-energy grazing incidence x-ray diffraction, x-ray reflectivity and x-ray photoelectron spectroscopy before and after annealing to 1400 K under ultra-high vacuum (UHV) conditions. The films were found to be epitaxial to the YSZ substrates, exhibiting good crystalline quality without defects like twinning, and low surface roughness. Upon reduction due to the annealing in ultrahigh vacuum (UHV), both samples showed an increase in lattice parameter while maintaining their original crystalline quality. The x-ray reflectivity measurements gave evidence for interdiffusion after annealing by the presence of an additional interfacial layer with reduced electron density. X-ray photoelectron spectroscopy revealed an increase in the concentration of Ce"3"+ and also yttrium at the surface upon annealing, indicating a slight reduction of the surface as well as diffusion of yttrium to the surface. - Highlights: • We demonstrate that Gadolinium doped Ceria films grow epitaxial on Yttria stabilized Zirconia in (111) and (110) orientation. • We show by high energy grazing incidence x-ray diffraction that the films are single crystalline and twinning free. • We give evidence that upon annealing the lattice expands as a result of oxygen vacancy formation. • We demonstrate the interface to the YSZ substrate is instable upon annealing to 1400 K. • X-ray photoemission proofs Yttrium segregation to the surface of the GDC films.