We study two-photon effects for a cavity quantum electrodynamics system where a waveguide is coupled to a cavity embedded in a two-level system. The wave function of two-photon scattering is exactly solved by using the Lehmann-Symanzik-Zimmermann reduction. Our results about quantum statistical properties of the outgoing photons explicitly exhibit the photon blockade effects in the strong-coupling regime. These results agree with the observations of recent experiments.

• Received 20 September 2010

DOI:https://doi.org/10.1103/PhysRevA.84.063803