phase retrieval microscopy, ptychography and microscopy with curved wave fronts.implementation of coherent scattering experiments in reflectivity mode (IRMA setup).Imperviousness to vibrations and thermal drifts over an extended energy rangeįTH imaging of magnetic domains with spatial resolution better than 50nm was achieved during the commissioning of the Sextants beamline.Versatile sample environments (magnetic fields, temperature, controlled atmosphere).High spatial resolution (potential sub 10 nm).The Sextants beamline hosts two reflectometers, RESOXS (low-T, high fields, ultra high vacuum) and IRMA (compact to fit in B working area, quick access in high vacuum). Imperviousness to strong or time dependent magnetic fields and to charging effects.High sensitivity (thin layers, diluted materials) and tunable probing depth (buried layers).Large magneto-optical effects at soft X-ray resonances.Sensitivity to magnetic structure (magnetization profile, roughness, domain size).Element selectivity and sensitivity to electronic properties.Inherent sensitivity to structural properties.Resolving power in excess of 5000 and up to 8000 on the optimized energy range.Possibility of band mapping with bulk sensitivity.Investigation of low-lying excitations associated with the ground state, analogous to optical spectroscopy, with element selectivity (intermediate state core-hole).Hihly correlated materials – magnetic materials.Detailed analysis of radiative decay channels following a resonant excitation.These are photon-in-photon-out resonant techniques, highly appropriate to the assessment of element specific magnetic properties under applied magnetic fields, with tunable bulk versus surface sensitivity. Coherent x-ray scattering and Fourier transform holography.X-ray resonant magnetic scattering (XRMS), 2 instruments.Resonant inelastic x-ray scattering (RIXS).The beamline will serve three types of experiment involving four instruments, three of them already financed through CNRS, ANR and cooperation with outside laboratories. Many experiments will be dealing with magnetic samples or involving orbital symmetry selection, thus helical undulators providing variable polarization have been specified. Finally, elastic scattering and diffraction experiments can require different conditions. Bendable mirrors will make it possible to adjust the focal distance, spotsize or beam divergence to the specific needs. A more symmetric spot (80 µm x 50 µm H x V) will provide optimum performance for coherent scattering. A very small vertical spot (~2 µm) will be necessary for high resolution inelastic scattering. Refocusing optics will be adapted to each experimental technique. Switching mirrors will enable the alternate use of the two branch lines. Further, a set of refocusing mirrors (some of them bendable) will be available to focus the beam to three distinct working areas at two branch lines. This will involve two tunable undulators in a medium-length straight section and a monochromator designed to provide a resolving power in excess of 10000 at full throughput in a ~ 20 µm x 80 µm spot at the exit slit. The flux at the sample position should exceed 1013 photons.s-1 over the optimized energy range. The purpose of the beamline is first and foremost to deliver the highest flux possible within a small focused beam over the 100 to 1000 eV spectral range, with good performance over an extended range going from 50 to 1700 eV.
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