Fabrication and characterization of zig-zag chains with photonic topological edges states

Recently, stimulated by discovery of topological phases of matter, research fields utilizing topological nature of systems has attracted a lot of attention. In photonics, photonic topological insulators mimicking topological insulators in material science have been proposed and demonstrated, leading to emergence of “topological photonics.” Photonic topological insulators were realized by using photonic crystals [1] and metamaterials [2], and exhibit exotic properties such as robustness against disorder and spin-locked non-dissipative propagation, which can be understood by analogies with topological insulators.