Simulation and detection of photonic Chern insulators in a one-dimensional circuit-QED lattice

We introduce a conceptually simple and experimentally feasible method to realize and detect photonic topological Chern insulators with a one-dimensional circuit quantum electrodynamics lattice. By periodically modulating the couplings in this lattice, we show that this one-dimensional model can be mapped into a two-dimensional Chern insulator model. In addition to allowing the study of photonic Chern insulators, this approach also provides a natural platform to realize experimentally Laughlin's pumping argument. Remarkably, based on the scattering theory of topological insulators and input-output formalism, we find that both the photonic edge state and topological invariant can be unambiguously probed with a simple dissipative few-resonator circuit-QED network.