title: Model-based magnetization retrieval from holographic phase images.
abstract: The phase shift of the electron wave is a useful measure for the projected magnetic flux density of magnetic objects at the nanometer scale. More important for materials science, however, is the knowledge about the magnetization in a magnetic nano-structure. As demonstrated here, a dominating presence of stray fields prohibits a direct interpretation of the phase in terms of magnetization modulus and direction. We therefore present a model-based approach for retrieving the magnetization by considering the projected shape of the nano-structure and assuming a homogeneous magnetization therein. We apply this method to FePt nano-islands epitaxially grown on a SrTiO3substrate, which indicates an inclination of their magnetization direction relative to the structural easy magnetic [001] axis. By means of this real-world example, we discuss prospects and limits of this approach.
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Institut für Ionenstrahlphysik und Materialforschung, Bautzner Landstr. 400, D-01328 Dresden, Germany; Triebenberg Labor, Institut für Strukturphysik, Technische Universität Dresden, D-01062 Dresden, Germany. Electronic address: f.roeder@hzdr.de.
authors.forename: Falk
authors.initials: F
authors.lastname: Röder
authors.affiliation: Triebenberg Labor, Institut für Strukturphysik, Technische Universität Dresden, D-01062 Dresden, Germany.
authors.forename: Karin
authors.initials: K
authors.lastname: Vogel
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Institut für Ionenstrahlphysik und Materialforschung, Bautzner Landstr. 400, D-01328 Dresden, Germany; Triebenberg Labor, Institut für Strukturphysik, Technische Universität Dresden, D-01062 Dresden, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wolf
authors.affiliation: Helmholtz-Zentrum Dresden-Rossendorf, Institut für Ionenstrahlphysik und Materialforschung, Bautzner Landstr. 400, D-01328 Dresden, Germany; AG Magnetische Funktionsmaterialien, Institut für Physik, Technische Universität Chemnitz, D-09126 Chemnitz, Germany; HGST, A Western Digital Company, 3403 Yerba Buena Rd., San Jose, CA 95135, USA.
authors.forename: Olav
authors.initials: O
authors.lastname: Hellwig
authors.affiliation: HGST, A Western Digital Company, 3403 Yerba Buena Rd., San Jose, CA 95135, USA.
authors.forename: Sung Hun
authors.initials: SH
authors.lastname: Wee
authors.affiliation: IFW Dresden, Institute for Metallic Materials, P.O. Box 270116, D-01171 Dresden, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Wicht
authors.affiliation: IFW Dresden, Institute for Metallic Materials, P.O. Box 270116, D-01171 Dresden, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Rellinghaus
keywords: FePt nano-structured film; Magnetic imaging; Off-axis electron holography