title: Atomic and electronic structure of the BaTiO3/Fe interface in multiferroic tunnel junctions.
abstract: Artificial multiferroic tunnel junctions combining a ferroelectric tunnel barrier of BaTiO(3) with magnetic electrodes display a tunnel magnetoresistance whose intensity can be controlled by the ferroelectric polarization of the barrier. This effect, called tunnel electromagnetoresistance (TEMR), and the corollary magnetoelectric coupling mechanisms at the BaTiO(3)/Fe interface were recently reported through macroscopic techniques. Here, we use advanced spectromicroscopy techniques by means of aberration-corrected scanning transmission electron microscopy (STEM) and electron energy-loss spectroscopy (EELS) to probe locally the nanoscale structural and electronic modifications at the ferroelectric/ferromagnetic interface. Atomically resolved real-space spectroscopic techniques reveal the presence of a single FeO layer between BaTiO(3) and Fe. Based on this accurate description of the studied interface, we propose an atomistic model of the ferroelectric/ferromagnetic interface further validated by comparing experimental and simulated STEM images with atomic resolution. Density functional theory calculations allow us to interpret the electronic and magnetic properties of these interfaces and to understand better their key role in the physics of multiferroics nanostructures.
authors.affiliation: Laboratoire de Physique des Solides, Bâtiment 510, CNRS UMR 8502, Université Paris Sud XI, 91405 Orsay, France.
authors.forename: Laura
authors.initials: L
authors.lastname: Bocher
authors.forename: Alexandre
authors.initials: A
authors.lastname: Gloter
authors.forename: Arnaud
authors.initials: A
authors.lastname: Crassous
authors.forename: Vincent
authors.initials: V
authors.lastname: Garcia
authors.forename: Katia
authors.initials: K
authors.lastname: March
authors.forename: Alberto
authors.initials: A
authors.lastname: Zobelli
authors.forename: Sergio
authors.initials: S
authors.lastname: Valencia
authors.forename: Shaïma
authors.initials: S
authors.lastname: Enouz-Vedrenne
authors.forename: Xavier
authors.initials: X
authors.lastname: Moya
authors.forename: Neil D
authors.initials: ND
authors.lastname: Mathur
authors.forename: Neil D
authors.initials: ND
authors.lastname: Marthur
authors.forename: Cyrile
authors.initials: C
authors.lastname: Deranlot
authors.forename: Stéphane
authors.initials: S
authors.lastname: Fusil
authors.forename: Karim
authors.initials: K
authors.lastname: Bouzehouane
authors.forename: Manuel
authors.initials: M
authors.lastname: Bibes
authors.forename: Agnès
authors.initials: A
authors.lastname: Barthélémy
authors.forename: Christian
authors.initials: C
authors.lastname: Colliex
authors.forename: Odile
authors.initials: O
authors.lastname: Stéphan
mesh_terms: D017609:Barium Compounds / Q000737:chemistry*; D004553:Electric Conductivity; D004579:Electron Transport; D007501:Iron / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012666:Semiconductors; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D017609:Barium Compounds; D046911:Macromolecular Substances; C024547:barium titanate(IV); D014025:Titanium; D007501:Iron