| AVS 63rd International Symposium & Exhibition | |
| Magnetic Interfaces and Nanostructures | Monday Sessions |
| Session MI+2D+AC-MoA |
| Session: | Magnetism and Spin Orbit Effects at Interfaces and Surfaces: Recent Experimental and Theoretical Advances |
| Presenter: | Lukasz Plucinski, FZ Jülich GmbH, Germany |
| Authors: | L. Plucinski, FZ Jülich GmbH, Germany M. Eschbach, FZ Jülich GmbH, Germany M. Lanius, FZ Jülich GmbH, Germany C. Niu, FZ Jülich GmbH, Germany E. Mlynczak, FZ Jülich GmbH, Germany P. Gospodaric, FZ Jülich GmbH, Germany J. Kellner, RWTH Aachen University, Germany P. Schüffelgen, FZ Jülich GmbH, Germany M. Gehlmann, FZ Jülich GmbH, Germany S. Döring, FZ Jülich GmbH, Germany E. Neumann, FZ Jülich GmbH, Germany M. Luysberg, FZ Jülich GmbH, Germany B. Holländer, FZ Jülich GmbH, Germany G. Mussler, FZ Jülich GmbH, Germany M. Morgenstern, RWTH Aachen University, Germany D. Grützmacher, FZ Jülich GmbH, Germany G. Bihlmayer, FZ Jülich GmbH, Germany S. Blügel, FZ Jülich GmbH, Germany Schneider, FZ Jülich GmbH, Germany |
| Correspondent: | Click to Email |
We present, a combined theoretical and experimental study on the prediction and verification of the dual topological insulating character of the stoichiometric natural superlattice phase Bi1Te1 = [Bi2]1[Bi2Te3]2 [1]. We identify Bi1Te1 by density functional theory to exhibit a non-trivial time-reversal symmetry-driven character of Z2 = (0; 001) and additionally a mirror-symmetry induced mirror Chern number of vM = -2, which indicates that Bi1Te1 is both a weak topological insulator (WTI) and a topological crystalline insulator (TCI). The coexistence of the two phenomena preordain distinct crystal planes to host topological surface states that are protected by the respective symmetries. From the analysis of time-reversal invariant momenta (TRIM-points) the surface perpendicular to the stacking direction, for instance, is found as the time-reversal symmetry dark surface, while hosting mirror-symmetry protected non-TRIM surface states along the surface-Gamma-M direction. We confirm the stacking sequence of our MBE-grown Bi1Te1 thin films by X-ray diffraction and transmission electron microscopy (STEM), and find clear indications of the TCI and WTI character in the surface electronic spin structure by spin- and angle-resolved photoemission spectroscopy.
[1] M. Eschbach et al., arXiv:1604.08886 (2016).