Topology protects light propagation in photonic crystal

Dutch researchers at AMOLF and TU Delft have seen light propagate in a special material without reflections. The material, a photonic crystal, consists of two parts that each have a slightly different pattern of perforations. Light can propagate along the boundary between these two parts in a special way: It is “topologically protected,” and therefore does not bounce back at imperfections. Even when the boundary forms a sharp corner, the light follows it without a problem. Continue reading…