Mapping out the emergence of topological features in the highly alloyed topological Kondo insulators Sm${}_{1-x}{M}_x$B${}_6$ ($M$=Eu, Ce)

Abstract

SmB6 is a strongly correlated material that has been attributed as a topological insulator and a Kondo insulator. Recent studies have found the topological surface states and low temperature insulating character to be profoundly robust against magnetic and non-magnetic impurities. Here, we use angle resolved photoemission spectroscopy to chart the evolution of topologically-linked electronic structure features versus magnetic doping and temperature in Sm${}_{1-x}$M${}_x$B${}_6$ (M=Eu, Ce). Topological coherence phenomena are observed out to unprecedented ~30% Eu and 50% Ce concentrations that represent extreme nominal hole and electron doping, respectively. Theoretical analysis reveals that a recent re-designation of the topologically inverted band symmetries provides a natural route to reconciling the persistence of topological surface state emergence even as the insulating gap is lost through decoherence.

References in corpus (7)

• Correlated Topological Insulators with Mixed Valence
• Direct observation of the spin texture in strongly correlated SmB6 as evidence of the topological Kondo insulator
• Kondo Breakdown in Topological Kondo Insulators
• 4$f$ crystal field ground state of the strongly correlated topological insulator SmB${}_6$
• Scanning tunneling spectroscopy and surface quasiparticle interference in models for the strongly correlated topological insulators SmB6 and PuB6
• Electronic structures of ferromagnetic superconductors ${\mathrm{UGe}}_2$ and $\mathrm{UCoGe}$ studied by angle-resolved photoelectron spectroscopy
• Kondo holes in topological Kondo insulators: Spectral properties and surface quasiparticle interference