Observation of photonic anomalous Floquet topological insulators
Observation of photonic anomalous Floquet topological insulators
Commonly, a two-dimensional topological insulator is characterized by non-zero Chern numbers associated with its band structure. In our work, we present the experimental demonstration of an anomalous topological insulator, for which the Chern numbers are always zero, and the winding number is the appropriate quantity describing the topological character of …