title: Strain driven monoclinic distortion of ultrathin CoO films in the exchange-coupled CoO/FePt/Pt(0 0 1) system.
abstract: The structure and strain of ultrathin CoO films grown on a Pt(0 0 1) substrate and on a ferromagnetic FePt pseudomorphic layer on Pt(0 0 1) have been determined with in situ and real time surface x-ray diffraction. The films grow epitaxially on both surfaces with an in-plane hexagonal pattern that yields a pseudo-cubic CoO(1 1 1) surface. A refined x-ray diffraction analysis reveals a slight monoclinic distortion at RT induced by the anisotropic stress at the interface. The tetragonal contribution to the distortion results in a ratio [Formula: see text], opposite to that found in the low temperature bulk CoO phase. This distortion leads to a stable Co(2+) spin configuration within the plane of the film.
authors.affiliation: Université Grenoble Alpes, Institut Néel, F-38042 Grenoble, France. CNRS, Institut Néel, F-38042 Grenoble, France.
authors.forename: Anne D
authors.initials: AD
authors.lastname: Lamirand
authors.forename: Márcio M
authors.initials: MM
authors.lastname: Soares
authors.forename: Maurizio
authors.initials: M
authors.lastname: De Santis
authors.forename: Aline Y
authors.initials: AY
authors.lastname: Ramos
authors.forename: Stéphane
authors.initials: S
authors.lastname: Grenier
authors.forename: Hélio C N
authors.initials: HC
authors.lastname: Tolentino