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We have analysed by use of synchrotron radiation induced angle resolved photoemission spectroscopy (PES), Auger electron spectroscopy (AES) and low-energy electron diffraction (LEED) the growth of ultrathin Co layers deposited at room temperature on Pt(111) surfaces. The LEED patterns indicate an incoherent epitaxy and AES data can be explained by a near layer by layer growth mode. Decomposition of the Pt 4f7/2 photoemission line shows characteristic core level shifts for the different environments of Pt atoms, giving insight concerning a relatively sharp interface structure. On the other hand, the Pt/Co interface in the Pt/Co/Pt(111) sandwich is less sharp, giving rise to two Pt surface sites. Annealing of the Co/Pt(111) system at 400 degrees C gives a surface alloy structure with the same symmetry and orientation as the Pt substrate.

At SOLEIL, Insertion Devices (IDs) performances are first evaluated with the electron beam commissioning then by the study of the radiation properties with the beamline. Spectra calculated from magnetic measurements with Synchrotron Radiation Workshop code and the ones measured on the beamline are compared. Even and odd harmonics width are measured and spatial distributions at a fixed energy are checked for several gap and phase values. Radiation properties are detailed in the cases of a 20 mm period planar in-vacuum undulator (U20), a 42 mm period APPLE II device (HU42) and a 80 mm period APPLE II device (HU80) generating non periodic magnetic fields components.

The magnetic exchange coupling in Co/α-Fe2O3(0001) interfaces has been studied. In this paper, we investigated magnetic properties at macroscopic (hysteresis loops) and microscopic (magnetic domain structure) scales. The system shows increased coercive fields and magnetic domain duplication likely mediated by the presence of a metallic interfacial Fe layer.