Characterization of the pairwise correlations in different quantum networks consisting of four-wave mixers and beamsplitters

Qi Jian¹, Xin Jun¹, Wang Hai-Long^{1, †}, Jing Jie-Tai^{1, 2, ‡}

(color online) FWM (BS) network. (a) FWM network. is the coherent input signal and is the vacuum input. is the amplified signal beam and is the generated idler beam. is the power gain of the FWM process. (b) BS network. is the coherent input signal and is the vacuum input. and are two output beams. is the transmission of the BS.