Date of Award
Doctor of Philosophy (PhD)
The structural and magnetic properties of ultrathin Fe/Ni(111)/W(110) films are investigated using LEED, two Auger electron spectroscopy techniques and magneto-optic Kerr magnetometry. A 2 ML Ni(111) buffer layer is used to grow fcc Fe(111) films to a thickness of 3 monolayers. The Ni substrate aIIows good wetting and lattice matching of the Fe without significant interfacial diffusion. Above 3ML a continuous structural transition from fcc to bcc is observed.
An electron energy analyser for use with a spin polarised low energy electron diffraction (SPLEED) electron spin analyser was designed and built. The energy analyser is used to study the growth mode and structure of ultrathin Fe/Ni(111)/W(110) films using angle resolved auger emission spectroscopy (ARAES). A method is developed to fit computer simulations to the ARAES data to determine the growth mode of ultrathin films.
Preliminary magnetic measurements of the fcc phase below 4 ML indicate that the Fe films are ferromagnetic with a magnetic moment perpendicular to the surface at coverages of 0.25 to 2.0 ML. At 2.5 ML a spin reorientation transition appears to occur and both perpendicular and in plane magnetic moments are observed. At 3.0 ML the magnetic moment is in the plane of the film.
Johnston, Hamish, "A Study of the Magnetic and Structural Properties of Ultrathin Fe/Ni(111)/W(110) Films" (1997). Open Access Dissertations and Theses. Paper 3321.