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arXiv · 1104.0966

Photoemission Spectroscopy of Magnetic and Non-magnetic Impurities on the Surface of the Bi$_2$Se$_3$ Topological Insulator

T. Valla·Z. -H. Pan·D. R. Gardner·Y. S. Lee·S. Chu
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Abstract

Dirac-like surface states on surfaces of topological insulators have a chiral spin structure that suppresses back-scattering and protects the coherence of these states in the presence of non-magnetic scatterers. In contrast, magnetic scatterers should open the back- scattering channel via the spin-flip processes and degrade the state's coherence. We present angle-resolved photoemission spectroscopy studies of the electronic structure and the scattering rates upon adsorption of various magnetic and non-magnetic impurities on the surface of Bi$_2$Se$_3$, a model topological insulator. We reveal a remarkable insensitivity of the topological surface state to both non-magnetic and magnetic impurities in the low impurity concentration regime. Scattering channels open up with the emergence of hexagonal warping in the high-doping regime, irrespective of the impurity's magnetic moment.

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T. Valla, Z. -H. Pan, D. R. Gardner, Y. S. Lee, S. Chu. 2012-03-12. Photoemission Spectroscopy of Magnetic and Non-magnetic Impurities on the Surface of the Bi$_2$Se$_3$ Topological Insulator. https://doi.org/10.1103/physrevlett.108.117601

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