title: Growth and electronic structure of Sm on thin Al2O3/Ni3Al(111) films.
abstract: The growth and electronic structure of vapor-deposited Sm on a well-ordered Al(2)O(3)/Ni(3)Al(111) ultrathin film under ultrahigh vacuum conditions at room temperature have been studied comprehensively using synchrotron radiation photoemission spectroscopy, X-ray photoelectron spectroscopy, work function measurements, scanning tunneling microscopy, and low-energy electron diffraction. Our results indicate that at room temperature Sm grows in a layer-by-layer fashion up to at least 1 ML, followed by three-dimensional growth. The interaction of Sm with Al(2)O(3) thin films leads to an initial oxidation of Sm, accompanied by a parallel reduction of the Al(2)O(3) substrate. Both the oxidation states of Sm(2+) and Sm(3+) are found at low coverage (<1 ML). The concentration of Sm(2+) saturates below 0.4 ML, while that of Sm(3+) keeps increasing until the metallic state of Sm appears at high coverages.
authors.affiliation: National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Xu
authors.forename: Shanwei
authors.initials: S
authors.lastname: Hu
authors.forename: Dingling
authors.initials: D
authors.lastname: Cheng
authors.forename: Xuefei
authors.initials: X
authors.lastname: Feng
authors.forename: Yong
authors.initials: Y
authors.lastname: Han
authors.forename: Junfa
authors.initials: J
authors.lastname: Zhu