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arXiv · 1312.5898

Band symmetries of mixed-valence topological insulator: SmB6

Chang-Jong Kang·Junwon Kim·Kyoo Kim·J. -S. Kang·J. D. Denlinger·B. I. Min
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Abstract

We have investigated the band structure and the band symmetry of mixed-valence insulator SmB$_{6}$ systematically within the density functional theory (DFT). We have analyzed the symmetries and characters of Sm $4f$ and $5d$ bands near the Fermi level ($E_F$) in terms of the non-relativistic real cubic bases as well as the relativistic complex bases incorporating the spin-orbit coupling and the cubic crystal field. Further, we have found that the semi-core band located at $\sim 15$ eV below $E_F$ has the mixed parity and thereby affects the parity eigenvalues of the special ${\bf k}$-points considerably. We have discussed the possible surface states and topological class of SmB$_{6}$, based on the bulk parity tables.

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Chang-Jong Kang, Junwon Kim, Kyoo Kim, J. -S. Kang, J. D. Denlinger, B. I. Min. 2013-12-20. Band symmetries of mixed-valence topological insulator: SmB6. https://doi.org/10.7566/jpsj.84.024722

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