Photonic Chern insulator through homogenization of an array of particles

Abstract

We propose a route towards creating a metamaterial that behaves as a photonic Chern insulator, through homogenization of an array of gyromagnetic cylinders. We show that such an array can exhibit nontrivial topological effects, including topologically nontrivial band gaps and one-way edge states, when it can be homogenized to an effective medium model that has the Berry curvature strongly peaked at the wave vector k=0. The nontrivial band topology depends only on the parameters of the cylinders and the cylinders' density, and can be realized in a wide variety of different lattices, including periodic, quasiperiodic, and random lattices. Our system provides a platform to explore the interplay between disorder and topology and also opens a route towards the synthesis of topological metamaterials based on the self-assembly approach.