Dresden 2014 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 105: Poster: Topological insulators (with MA/O)
HL 105.12: Poster
Thursday, April 3, 2014, 17:00–20:00, P1
Combined XMCD and STS study of transition metal adatoms adsorbed on the surface of prototypical 3D topological insulators — •Jonas Warmuth1, Martin Vondráček2, Matteo Michiardi3, Lucas Barreto3, Cinthia Piamonteze4, Andreas Eich1, Alexander Khajetoorians1, Jan Honolka2, Jian-Li Mi3, Bo Brummerstedt Iversen3, Philip Hofmann3, Jens Wiebe1, and Roland Wiesendanger1 — 1Institute of Applied Physics, Uni Hamburg, Germany — 2Institute of Physics ASCR, Prague, Czech Republic — 3iNano, Aarhus University, Denmark — 4Laboratory of Condensed Matter Physics, PSI, Switzerland
The spin of Dirac electrons in topological surface states is rigidly locked to the direction of their momentum leading, e.g., to prohibited backscattering. Their interaction with magnetic impurities is currently a matter of debate, because it can destroy this effect, heavily depending on the magnetic properties of the impurities. Using x-ray magnetic circular dichroism techniques we investigated 3d transition metal adatoms adsorbed on the surface of different prototypical 3D topological insulators. We compare our results to crystal field multiplet calculations [1] of the 3d states. For some of the adatom species, we find a considerable magnetic anisotropy, which depends crucially on the coupling of their 3d states to the substrate electrons. Furthermore, we investigate the interaction of the adatoms and the Dirac electrons by Fourier-transform scanning tunneling spectroscopy [2], which reveals shifts of the linear dispersion due to surface doping effects.
J. Honolka et al., PRL 108, 256811 (2012)