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arXiv · 0910.4604

Impurity-induced states on the surface of 3D topological insulators

Rudro R. Biswas·Alexander V. Balatsky
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Abstract

We calculate the modification of the local electronic structure caused by a local impurity on the surface of a 3D Topological Insulator. We find that the LDOS around the Dirac point of the electronic spectrum at the surface is significantly disrupted near the impurity by the creation of low-energy resonance state(s) -- however, this is not sufficient to (locally) destroy the Dirac point. We also calculate the non-trivial spin textures created near the magnetic impurities and discover anisotropic RKKY coupling between them.

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Rudro R. Biswas, Alexander V. Balatsky. 2009-10-26. Impurity-induced states on the surface of 3D topological insulators. https://doi.org/10.1103/physrevb.81.233405

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