We propose a scheme to realize a topological insulator with optical-passive
elements, and analyze the effects of Kerr-nonlinearities in its topological
behavior. In the linear regime, our design gives rise to an optical spectrum
with topological features and where the bandwidths and bandgaps are
dramatically broadened. The resulting edge modes cover a very wide frequency
range. We relate this behavior to the fact that the effective Hamiltonian
describing the system's amplitudes is long-range. We also develop a method to
analyze the scheme in the presence of a Kerr medium. We assess robustness and
stability of the topological features, and predict the presence of chiral
squeezed fluctuations at the edges in some parameter regimes.Comment: 18 pages, 9 figure
