Die u:cris Detailansicht:
Observation of hidden atomic order at the interface between Fe and topological insulator Bi2Te3
- Autor(en)
- Jaime Sanchez-Barriga, Ilya I. Ogorodnikov, Mikhail V. Kuznetsov, Andrey A. Volykhov, Fumihiko Matsui, Carolien Callaert, Joke Hadermann, Nikolay I. Verbitskiy, Roland J. Koch, Andrei Varykhalov, Oliver Rader, Lada V. Yashina
- Abstrakt
To realize spintronic devices based on topological insulators (TIs), well-defined interfaces between magnetic metals and TIs are required. Here, we characterize atomically precisely the interface between the 3d transition metal Fe and the TI Bi
2Te
3 at different stages of its formation. Using photoelectron diffraction and holography, we show that after deposition of up to 3 monolayers Fe on Bi
2Te
3 at room temperature, the Fe atoms are ordered at the interface despite the surface disorder revealed by our scanning-tunneling microscopy images. We find that Fe occupies two different sites: a hollow adatom deeply relaxed into the Bi
2Te
3 quintuple layers and an interstitial atom between the third (Te) and fourth (Bi) atomic layers. For both sites, our core-level photoemission spectra and density-functional theory calculations demonstrate simultaneous chemical bonding of Fe to both Te and Bi atoms. We further show that upon deposition of Fe up to a thickness of 20 nm, the Fe atoms penetrate deeper into the bulk forming a 2-5 nm interface layer containing FeTe. In addition, excessive Bi is pushed down into the bulk of Bi
2Te
3 leading to the formation of septuple layers of Bi
3Te
4 within a distance of ∼25 nm from the interface. Controlling the magnetic properties of the complex interface structures revealed by our work will be of critical importance when optimizing the efficiency of spin injection in TI-based devices.
- Organisation(en)
- Elektronische Materialeigenschaften
- Externe Organisation(en)
- Helmholtz-Zentrum Berlin für Materialien und Energie, Russian Academy of Sciences, Lomonosov Moscow State University (MSU), Nara Institute of Science and Technology (NAIST), University of Antwerp, Lawrence Berkeley National Laboratory
- Journal
- Physical Chemistry Chemical Physics
- Band
- 19
- Seiten
- 30520-30532
- Anzahl der Seiten
- 13
- ISSN
- 1463-9076
- DOI
- https://doi.org/10.1039/c7cp04875k
- Publikationsdatum
- 12-2017
- Peer-reviewed
- Ja
- ÖFOS 2012
- 104006 Festkörperchemie, 103018 Materialphysik, 103009 Festkörperphysik, 103020 Oberflächenphysik
- Schlagwörter
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/39caf9e0-7047-4d6c-8ca2-97349ab30203