Controllable photon blockade in double-cavity optomechanical system with Kerr-type nonlinearity

Photon blockade (PB) is an effective way to generate single photon source which is indispensable in single-photon-based quantum information processing. Here we investigate the statistical properties of photons in a double-cavity optomechanical system, in which an optomechanical cavity (the primary one) is coupled to a Kerr-nonlinearity cavity (the secondary one). The optimal parametric relations for a strong PB effect are derived by calculating the equal-time second-order correlation functions. The results show that a weak Kerr-nonlinearity leads to a perfect PB effect in the primary cavity and a strong Kerr-nonlinearity leads to a stronger PB effect in the secondary cavity and between the two cavities. By adjusting the tunneling coupling strength to satisfy the optimal parametric conditions, the antibunching effects in and between these two cavities are controllable by properly selecting the Kerr-nonlinearity strength. This system can be used for a single-photon source with a controllable fashion in quantum information processing.