A Strongly-Interacting Dirac Liquid on the Surface of a Topological Kondo Insulator

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 non-trivial 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.

6 pages, 1 figure; Minor changes. Published version

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Cited by in corpus (6)

• Kondo Breakdown in Topological Kondo Insulators
• Two-dimensional heavy fermions on the strongly correlated boundaries of Kondo topological insulators
• Magnetic skyrmion crystal at a topological insulator surface
• Flat and Correlated Plasmon Bands in Graphene/$\alpha$-RuCl${}_3$ Heterostructures
• Optical conductivity of topological Kondo insulating states
• Many-Body Effects in Topological Kondo Insulators