Compound photon blockade based on three mode system

Based on the four wave mixing, a three mode nonlinear system is proposed. The single photon blockade is discussed through analytical analysis and numerical calculation. The analytical analysis shows that the conventional photon blockade and unconventional photon blockade can be realized at the same time, and the analytical conditions of the two kinds of blockade are the same. The numerical results show that the system not only has the maximum average photon number in the blockade region, but also can have strong photon anti-bunching in the region with small nonlinear coupling coefficient, which greatly reduces the experimental difficulty of the system. This optical system which can realize the compound photon blockade effect is helpful to realize the high-purity single photon source.