title: In Depth Spatially Inhomogeneous Phase Transition in Epitaxial MnAs Film on GaAs(001).
abstract: Most studies on MnAs material in its bulk form have been focused on its temperature-dependent structural phase transition accompanied by a magnetic one. Magnetostructural phase transition parameters in thin MnAs films grown on substrates present however some differences from the bulk behavior, and local studies become mandatory for a deeper understanding of the mechanisms involved within the transition. Up to now, only surface techniques have been carried out, while the transition is a three-dimensional phenomenon. We therefore developed an original nanometer scale methodology using electron holography to investigate the phase transition in an epitaxial MnAs thin film on GaAs(001) from the cross-section view. Using quantitative magnetic maps recorded at the nanometer scale as a function of the temperature, our work provides a direct in situ observation of the inhomogeneous spatial distribution of the transition in the layer depth and brings new insights on the fundamental transition mechanisms.
authors.affiliation: CEMES CNRS-UPR 8011, Université de Toulouse , 31055 Toulouse, France.
authors.forename: C
authors.identifier: 0000-0001-5549-7008
authors.initials: C
authors.lastname: Gatel
authors.affiliation: CEMES CNRS-UPR 8011, Université de Toulouse , 31055 Toulouse, France.
authors.forename: X
authors.initials: X
authors.lastname: Fu
authors.affiliation: CEMES CNRS-UPR 8011, Université de Toulouse , 31055 Toulouse, France.
authors.forename: V
authors.initials: V
authors.lastname: Serin
authors.affiliation: INSP CNRS-UMR 7588, Sorbonne Universités-UPMC 75252 Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Eddrief
authors.affiliation: LISV, Université Versailles St-Quentin , 78140 Vélizy, France.
authors.forename: V
authors.initials: V
authors.lastname: Etgens
authors.affiliation: CEMES CNRS-UPR 8011, Université de Toulouse , 31055 Toulouse, France.
authors.forename: B
authors.initials: B
authors.lastname: Warot-Fonrose
keywords: Electron holography; MnAs; in situ TEM; magnetic materials; phase transition; thin film