Termination-dependent Surface In-gap States in a Mixed-valent Topological Insulator: SmB${}_6$

Abstract

We have investigated the surface states of a potential mixed-valent topological insulator SmB${}_6$ based on the first principles density functional theory slab band structure analysis. We have found that metallic surface states are formed in the bulk band gap region, providing evidence for the topological insulating nature of SmB${}_6$. The obtained surface in-gap states are quite different from those in existing reports in that they are formed differently depending on the Sm or B${}_6$ surface termination, and are composed of mainly Sm $4f$ state indicating the essentiality of including $f$ electrons in describing the surface states. We have obtained the spin chiral structures of the Fermi surfaces, which are also in accordance with the topological insulating nature of SmB${}_6$.

References in corpus (1)

• Correlated Topological Insulators with Mixed Valence

Cited by in corpus (5)

• Additional energy scale in SmB${}_6$ at low temperature
• Topological properties and the dynamical crossover from mixed-valence to Kondo-lattice behavior in golden phase of SmS
• Spin- and angle-resolved photoemission on the topological Kondo Insulator candidate: SmB6
• Planar tunneling spectroscopy of the topological Kondo insulator SmB${}_6$
• Topological nature of the Kondo insulator SmB${}_6$ and its sensitiveness to Sm vacancy