2020/06/11 by Alexander Cerjan, Marius Jürgensen, Wladimir A. Benalcazar +2 · 1 citation
Physics and Astronomy · #physics.optics #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.125.213901
published as Phys. Rev. Lett. 125, 213901 (2020) · 6 pages, 4 figures, 2 pages supplementary information
arxiv created 2020/06/11 · arxiv updated 2020/11/25
Higher-order topological insulators are a recently discovered class of materials that can possess zero-dimensional localized states regardless of the dimension of the lattice. Here, we experimentally demonstrate that the topological corner-localized modes of higher-order topological insulators can be symmetry protected bound states in the continuum; these states do not hybridize with the surrounding bulk states of the lattice even in the absence of a bulk bandgap. As such, this class of structures has potential applications in confining and controlling light in systems that do not support a complete photonic bandgap.