Abstract

With regard to the system of parametric downconversion, we analyze a recently proposed experiment for demonstrating the nonlocal property of a single photon.¹ In the original proposal by Tan et al., a light field in a single photon-number state is split into two beams, which are then homodyned with two spatially separated weak local oscillators. The two-photon detection probability with the two homodyned beams provides evidence for nonlocality. It is shown that this phenomenon is in essence a phase-sensitive fourth-order interference effect. A single photonnumber state can be achieved from the pair of photons produced in parametric downconversion processes.² A multimode model for the downconversion process is used to carry out the calculation of three-photon detection probability that is associated with nonlocality of a single photon.

© 1991 Optical Society of America