Experimental Characterization of the Deterministic Interface States in Two-Dimensional Photonic Crystals

The study of interface/surface states in photonic crystals provides new approaches to control the flow of light. In this work, a new type of interface states in two-dimensional photonic crystals is experimentally realized and characterized [1]. The existence of this type of interface states is solely dependent on the reflection properties of the bulk photonic crystals without any surface/interface decorations. Our experimental results have excellent agreement to numerical simulations and the propagation properties of these measured interface states indicate that this new type of interface states will be a good candidate for future optical waveguiding applications. This type of deterministic interface states also exists at the boundary between a dielectric photonic crystal and its “inverted” partner as long as a common gap can be found above the lowest band, which is also experimentally characterized [2].