AVS 45th International Symposium
    Magnetic Interfaces and Nanostructures Technical Group Thursday Sessions
       Session MI-ThA

Paper MI-ThA9
The Effect of Oxygen on the Growth and the Surface Magnetism of Iron Films

Thursday, November 5, 1998, 4:40 pm, Room 324/325

Session: Structure & Magnetism of Surfaces & Interfaces
Presenter: L. Mattera, University of Genova, Italy
Authors: R. Moroni, University of Genova, Italy
F. Bisio, University of Genova, Italy
M. Salvietti, University of Genova, Italy
M. Canepa, University of Genova, Italy
L. Mattera, University of Genova, Italy
Correspondent: Click to Email
The effect of oxygen on the growth and the surface magnetism of iron films has been investigated by Helium Reflectivity (HR) and Spin Polarized Metastable Deexcitation Spectroscopy (SPMDS) during the growth of Fe on an O(1X1)-Fe adlayer. HR and SPMDS measurements are performed contemporarily, providing real time information on defect density (HR) and electronic and magnetic properties (SPMDS) at surface as the growth proceeds. At room temperature, on O(1X1)-Fe, iron grows layer-by-layer, the oxygen atoms acting as surfactants. The intensity of the features induced by O@sub 2p@ and Fe@sub 3d@ states in the electron distribution curves detected following the deexcitation of metastable atoms remain unchanged during the growth indicating that the surface composition is constant: the oxygen atoms remain segregated at surface by position exchange with incoming iron atoms. Helium reflectivity and magnetization intensity oscillate in-phase during growth: significant oscillations of the magnetization intensity are observed in perfect phase with the cyclic order/disorder transitions. Such a behaviour provides a real time, direct experimental evidence of the strong correlation between structural order and magnetization intensity.