Temporally Correlated Narrowband Biphoton Interference Based on Mach–Zehnder Interferometer

Since early 1990s, Mach–Zehnder interferometer has been used to investigate the interference of biphoton wave packets. Due to subpicosecond time coherence of biphoton generated by spontaneous parametric downconversion process, some physical processes are ignored in the interferometer, most likely the biphoton time-domain interference. Here, the two-photon interference phenomenon based on the Mach–Zehnder interferometer is theoretically studied, where the correlated photon pairs are produced by the four-wave mixing in atomic system. In particular, the quantum interference effect to effectively control the coherent time of two-photon by adjusting the input delay is used. In the damped Rabi oscillation regime, two-photon bunching and antibunching effects are observed. In addition, in the group-delay regime, the interference between biphoton precursor, slow-light wave packets and also in between the precursor and the slow-light wave packets is observed, which had never been reported before. These results may have potential applications in the fields of biphoton shaping and quantum information processing.