Topological insulators in filled skutterudites

Understand

We propose new topological insulators in cerium filled skutterudite (FS) compounds based on ab initio calculations.

• We find that two compounds CeOs4As12 and CeOs4Sb12 are zero gap materials with band inversion between Os-d and Ce-f orbitals, which are thus parent compounds of two and three-dimensional topological insulators just like bulk HgTe.
• At low temperature, both compounds become topological Kondo insulators, which are Kondo insulators in the bulk, but have robust Dirac surface states on the boundary.
• This new family of topological insulators has two advantages compared to previous ones.