From blockade to transparency: controllable photon transmission through a circuit QED system
A strong photon-photon nonlinear interaction is a necessary condition for photon blockade. Moreover, this nonlinearity can also result a bistable behavior in the cavity field. We analyze the relation between detecting field and photon blockade in a superconducting circuit QED system, and show that the photon blockade cannot occur when the detecting field is in the bistable regime. We further demonstrate that the photon transmission through such system can be controlled (from photon blockade to transparency) by the detecting field. Numerical simulations show that our proposal is experimentally realizable with current technology.