Dresden 2009 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 32: Surface or interface magnetism
O 32.3: Vortrag
Mittwoch, 25. März 2009, 11:00–11:15, SCH A315
Depth-resolved photoemission studies on the system MgO/Fe — •Sven Döring1, 2, Frank Schönbohm1, 2, Ulf Berges1, 2, See-Hun Yang3, Christian Papp3, 4, Benjamin Balke3, 4, Reinert Schreiber5, Daniel E. Bürgler5, Claus M. Schneider5, Charles S. Fadley3, 4, and Carsten Westphal1, 2 — 1DELTA, TU Dortmund, Maria-Goeppert-Mayer-Str. 2, 44221 Dortmund, Germany — 2Experimentelle Physik 1, TU Dortmund, Otto-Hahn-Str. 4, 44221 Dortmund, Germany — 3Materials and Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA — 4University of California, Davis, CA 95616, USA — 5Jülich Forschungszentrum, IFF-9, 52425 Jülich, Germany
A high depth-resolution in photoemission experiments can be obtained by exciting the photoemission process with nm-scale x-ray standing waves above a multilayer mirror (e.g. Yang et al., J. Appl. Phys. 103, 07C519 (2008)). With this technique, we investigated a model MgO/Fe magnetic tunnel junction, in particular exploring the degree of Fe oxidation at the interface between the two layers, which is thought to critically affect the tunnel magnetoresistance.. With the Fe in a wedge profile, the MgO-Fe interface can be moved through the standing wave field by moving the sample relative to the beam. The experiments were performed at DELTA (Dortmund), the ALS (Berkeley), and BESSY II (Berlin). Such standing wave/wedge scans, as well as rocking curves, allow us to develop a depth-profile of our sample. As one preliminary conclusion, we find no evidence for the presence of iron oxide at the interface.