Filling of magnetic-impurity-induced gap in topological insulators by potential scattering

Abstract

We show that the energy gap induced by ferromagnetically aligned magnetic impurities on the surface of a topological insulator can be filled, due to scattering off the non-magnetic potential of the impurities. In both a continuum surface model and a three-dimensional tight-binding lattice model, we find that the energy gap disappears already at weak potential scattering as impurity resonances add spectral weight at the Dirac point. This can help explain seemingly contradictory experimental results as to the existence of a gap.

5 pages, 4 figures. Published version

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Cited by in corpus (4)

• Distinct Effects of Cr Bulk Doping and Surface Deposition on the Chemical Environment and Electronic Structure of the Topological Insulator Bi2Se3
• Nature of the Dirac gap modulation and surface magnetic interaction in axion antiferromagnetic topological insulator MnBi${}_2$Te${}_4$
• Phonon and defect mediated quantum anomalous Hall insulator to metal transition in magnetically doped topological insulators
• Doping-controlled surface conduction in topological insulators with warping effects