Second-order interference of two independent and tunable single-mode continuous-wave lasers

Liu Jianbin^{1, 2}, Wei Dong^{3, †,}, Chen Hui^{1, 2}, Zhou Yu³, Zheng Huaibin^{1, 2, 3}, Gao Hong³, Li Fu-Li³, Xu Zhuo^{1, 2}

Simulated two-photon coincidence counting rates when the frequency difference varies. R_cc: two-photon coincidence counting rate. t₁ − t₂: time difference between two single-photon detection event for a two-photon coincidence count. The parameters for the simulation are as follows. Central wavlength: 780 nm, frequency bandwidth: 100 kHz, resolution time: 0.35 ns, channel width: 0.0122 ns. Time window: 40 ns. (a)–(h) correspond to the frequency difference between these two lasers are 0.1, 0.2 0.5, 1, 2, 2.86, 5, 10 GHz, respectively.