Strongly interacting Dirac liquid on the surface of a topological Kondo insulator

Dmitry K. Efimkin, Victor Galitski

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14 Citations (Scopus)

Abstract

A topological Kondo insulator (TKI) is a strongly correlated material, where hybridization between the conduction electrons and localized f electrons gives rise to a crossover from a metallic behavior at high temperatures to a topologically nontrivial insulating state at low temperatures. The existing description of the TKIs is based on a slave-boson mean-field theory, which neglects dynamic fluctuation phenomena. Here, we go beyond the mean-field theory and investigate the role of Kondo fluctuations on the topological surface states. We derive an effective theory of the Dirac surface states coupled to fluctuations and show that the latter mediate strong repulsive interactions between surface excitations. We show that these effects renormalize the plasmon spectrum on the surface. We also argue that Kondo-mediated interactions may drive a magnetic instability of the surface spectrum.

Original languageEnglish
Article number081113
Number of pages5
JournalPhysical Review B
Volume90
Issue number8
DOIs
Publication statusPublished - 21 Aug 2014
Externally publishedYes

Keywords

  • Insulators
  • Hybridization gap
  • Surfaces

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