Bulk-interface correspondences for one-dimensional topological materials with inversion symmetry

Abstract

The interface between two materials described by spectrally gapped Hamiltonians is expected to host an in-gap interface mode, whenever a certain topological invariant changes across the interface. We provide a precise statement of this bulk-interface correspondence and its rigorous justification. The correspondence applies to continuum and lattice models of interfaces between one-dimensional materials with inversion symmetry, with dislocation models being of particular interest. For continuum models, the analysis of the parity of the ‘edge’ Bloch modes is the key component in our argument, while for the lattice models, the relative Zak phase and index theory are.