Topology of SmB$_6$ determined by dynamical mean field theory

Abstract

Whether SmB6 is a topological insulator remains hotly debated. Our density functional theory plus dynamical mean field theory calculations are in excellent agreement with a large range of experiments, from the 4f5.5 intermediate valency to x-ray and photoemission spectra. Using the pole extended (PE) Hamiltonian, which fully captures the self-energy, we show that SmB6 is a strongly correlated topological insulator, albeit not a Kondo insulator. The PE Hamiltonian is proved to be topological (in)equivalent to the topological Hamiltonian for (non-)local self-energies. The topological surface states are analyzed, addressing conflicting interpretations of photoemission data.