Band topology in classical waves: Wilson-loop approach to topological numbers and fragile topology
Journal
New Journal of Physics
Journal Volume
21
Journal Issue
9
Date Issued
2019
Author(s)
Wang H.-X., Guo G.-Y., Jiang J.-H.
Abstract
The rapid development of topological photonics and acoustics calls for accurate understanding of band topology in classical waves, which is not yet achieved in many situations. Here, we present the Wilson-loop approach for exact numerical calculation of the topological invariants for several photonic/sonic crystals. We demonstrate that these topological photonic/sonic crystals are topological crystalline insulators with fragile topology, a feature which has been ignored in previous studies. We further discuss the bulk-edge correspondence in these systems with emphasis on symmetry broken on the edges. ? 2019 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft.
Subjects
Physics; Research; Berry phase; Classical waves; Crystalline insulators; Numerical calculation; Topological invariants; Topological number; Topological photonics/acoustics; Wilson loops; Topology
SDGs
Type
journal article