Ultrathin Magnetic Oxides

We investigate the atomic and magnetic structure of ultra-thin oxide films and surfaces [1-3]. The left part of the figure shows the structure model of the (2x1) reconstructed (001) surface of bulk Bariumtitanate (BaTiO3) [3]. It is characterized by a fivefold coordinated Ti-atom (labelled by #5), residing in a tetragonal pyramid with oxygen atoms (red) labelled 8, 8’, 7, 7’ and 4. Ab initio calculations based on this model predict surface metallization and large local magnetic moments as shown on the right. 

Surface Structure and Magnetism - Fig. 2