Two-photon interferences with degenerate and nondegenerate paired photons
Chang Liu, J. F. Chen, Shanchao Zhang, Shuyu Zhou, Yoon-Ho Kim, M. M. T. Loy, G. K. L. Wong, Shengwang Du · Physical Review A · 2012
We generate narrow-band frequency-tunable entangled photon pairs from spontaneous four-wave mixing in three-level cold atoms and study their two-photon quantum interference after a beam splitter. We find that the path-exchange symmetry plays a more important role in the Hong-Ou-Mandel interference than the temporal or frequency indistinguishability, and observe coalescence interference for both degenerate and nondegenerate photons. We also observe a quantum beat in the same experimental setup using either slow or fast detectors.