Topology invisible to eigenvalues in obstructed atomic insulators

Abstract

Although symmetry indicators are a powerful new tool for identifying band topology, they do not tell the whole story. Here, the authors study pairs of atomic limit phases where the locations of Wannier orbitals differ, even though they share the same symmetry data (irreps) everywhere in the Brillouin zone. The authors give examples of such phases and show how Berry phase invariants can be used to distinguish between them. Finally, the authors classify all such ``irrep-equivalent'' atomic limit phases using band representations.

Topics & Concepts