Nonlinear effect on the transmission of light in a cavity array

Taking nonlinear effect into account, we study theoretically the transmission properties of photons in a one-dimensional coupled cavities, the cavity located at the center of the cavity array is coupled to a two-level system. By the traditional scattering theory, we calculate the transmission rate of photons along the cavities, and discuss the effect of nonlinearity on the photon transport. The results show that the controllable two-level system can act as a quantum switch in the coherent transport of photons. The dynamics of such a system is also studied by numerical simulations, the effect of the atom-field detuning and nonlinearity on the dynamics is shown and discussed.