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arXiv · 1403.3566

Kondo holes in topological Kondo insulators: Spectral properties and surface quasiparticle interference

Pier Paolo Baruselli·Matthias Vojta
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Abstract

A fascinating type of symmetry-protected topological states of matter are topological Kondo insulators, where insulating behavior arises from Kondo screening of localized moments via conduction electrons, and non-trivial topology emerges from the structure of the hybridization between the local-moment and conduction bands. Here we study the physics of Kondo holes, i.e., missing local moments, in three-dimensional topological Kondo insulators, using a self-consistent real-space mean-field theory. Such Kondo holes quite generically induce in-gap states which, for Kondo holes at or near the surface, hybridize with the topological surface state. In particular, we study the surface-state quasiparticle interference (QPI) induced by a dilute concentration of surface Kondo holes and compare this to QPI from conventional potential scatterers. We treat both strong and weak topological-insulator phases and, for the latter, specifically discuss the contributions to QPI from inter-Dirac-cone scattering.

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Pier Paolo Baruselli, Matthias Vojta. 2014-03-14. Kondo holes in topological Kondo insulators: Spectral properties and surface quasiparticle interference. https://doi.org/10.1103/physrevb.89.205105

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