OPTICAL RESONATOR ANALOG OF A PHOTONIC TOPOLOGICAL INSULATOR: A FINITE-DIFFERENCE TIME-DOMAIN STUDY

A periodic lattice of optical ring resonators can act as a photonic topological insulator, with the role of spin played by the direction of propagation of light within each ring. Using finite-difference time-domain (FDTD) simulations, we compute the projected band diagram of the system and its transmission spectrum, and demonstrate the existence of the topological edge states. The FDTD results are in good agreement with the predictions of transfer matrix theory.