Regensburg 2013 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 35: Poster Session I (Metal, semiconductor and oxide substrates: structure and adsorbates; Graphene)

O 35.50: Poster

Dienstag, 12. März 2013, 18:15–21:45, Poster B1

Density functional calculations for SrTiO₃(001) and Fe/SrTiO₃ — •Brahim Belhadji and Eckhard Pehlke — Institut für Theoretische Physik und Astrophysik, Universität Kiel

Magnetoelectric coupling at, e.g., the interface of magnetic d-metals and BaTiO₃ [1] has attracted a lot of interest also in view of applications, like sensors. The magnetization of thin Fe-films on BaTiO₃ or SrTiO₃ has been shown to depend even qualitatively on the number of Fe-layers [2]. The comparison of d-metals on BaTiO₃ and SrTiO₃ will open up the opportunity to compare different contributions to the magnetoelectric coupling mechanism at such interfaces. As a first step we have studied the clean (001) surface of SrTiO₃. The electronic structure is calculated using VASP code. We focus on the experimentally observed √5×√5 reconstruction and compare the Sr-adatom model proposed in [3] and the surface atomic geometry proposed in [4] (and two simple (1× 1) surface terminations as a reference). Scanning tunneling microscopy images are simulated within the Tersoff-Hamann model for both surfaces and various voltages. Furthermore we report first calculations for a single up to few monolayers of Fe on the (001) surface of SrTiO₃ and compare to previous work [2]. This lays the basis for a future study of magnetoelectric coupling mechanisms in case of thin d-metal films on these titanates.
[1] Chun-Gang Duan et al. PRL 97 (047201)(2006).
[2] M. Fechner et al. PRB 78, 212406 (2008).
[3] T. Kubo et al. PRL 86, 1801 (2001).
[4] D. M. Kienzle et al. PRL 106, 176102 (2011).