Hybridization, Inter-Ion Correlation, and Surface States in the Kondo Insulator SmB_{6}

As an exemplary Kondo insulator, SmB_{6} has been studied for several decades. However, direct evidence for the development of the Kondo coherent state and for the evolution of the electronic structure in the material has not been obtained due to the compound’s rather complicated electronic and ther...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Xiaohang Zhang, N. P. Butch, P. Syers, S. Ziemak, Richard L. Greene, Johnpierre Paglione
Formato: article
Lenguaje:EN
Publicado: American Physical Society 2013
Materias:
Acceso en línea:https://doaj.org/article/99d6050858a54f1bb6402d268f55b61d
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:As an exemplary Kondo insulator, SmB_{6} has been studied for several decades. However, direct evidence for the development of the Kondo coherent state and for the evolution of the electronic structure in the material has not been obtained due to the compound’s rather complicated electronic and thermal transport behavior. Recently, these open questions have attracted increasing attention as the emergence of a time-reversal-invariant topological surface state in the Kondo insulator has been suggested. Here, we use point-contact spectroscopy to reveal the temperature dependence of the electronic states in SmB_{6}. We demonstrate that SmB_{6} is a model Kondo insulator: Below 100 K, the conductance spectra reflect the Kondo hybridization of Sm ions, but, below about 30  K, signatures of inter-ion correlation effects clearly emerge. Moreover, we find evidence that the low-temperature insulating state of this exemplary Kondo-lattice compound harbors conduction states on the surface, in support of predictions of nontrivial topology in Kondo insulators.