Journal of Vacuum Science & Technology A, Vol.16, No.3, 1348-1354, 1998
Characterization and photoemission dichroism of epitaxially grown Gd(0001)/Y(0001)
Gadolinium thin films approximately 100 Angstrom thick have been grown epitaxially on a Y(0001) substrate. A threefold characterization has been performed. The surface structural analyses of the yttrium substrate and the gadolinium films were performed using x-ray photoelectron diffraction (XPD) and low-energy electron diffraction (LEED). The results of the XPD and LEED studies strongly suggest that gadolinium films have an effective C-6v Surface symmetry, consistent with earlier studies of other hcp (0001) surfaces. The elemental analysis of the substrate and the film was done with x-ray photoemission using Mg, Al K alpha x rays and synchrotron radiation. The magnetic analysis is based upon magnetic x-ray dichroisms observed in angle-resolved photoelectron spectroscopy, using both Linearly polarized and circularly polarized synchrotron x-ray radiation as the excitation. Photoemission from the Gd 4f and 5p core-level states were used in this magnetic characterization and will be presented. This includes novel magnetic linear dichroism angular distribution results for the Gd 5p, which exhibit up to 40% asymmetry, on a par with the previously reported circular dichroism results.
Keywords:CORE-LEVEL PHOTOEMISSION;MAGNETIC CIRCULAR-DICHROISM;LINEARLY POLARIZED-LIGHT;X-RAY DICHROISM;PHOTOELECTRON-SPECTROSCOPY;FINE-STRUCTURE;SURFACE;FILMS;DIFFRACTION;GD