2020/01/23 by Qiang Wang, Haoran Xue, Baile Zhang +1 · 1 citation
Physics and Astronomy · #cond-mat.mes-hall #physics.optics
paper · pdf · doi:10.1103/physrevlett.124.243602
published as Phys. Rev. Lett. 124, 243602 (2020)
arxiv created 2020/01/23 · arxiv updated 2020/07/01
Topological defects (TDs) in crystal lattices are elementary lattice imperfections that cannot be removed by local perturbations, due to their real space topology. We show that adding TDs into a valley photonic crystal generates a lattice disclination that acts like a domain wall and hosts topological edge states. The disclination functions as a freeform waveguide connecting a pair of TDs of opposite topological charge. This interplay between the real-space topology of lattice defects and band topology provides a novel scheme to implement large-scale photonic structures with complex arrangements of robust topological waveguides and resonators.