Abstract

An analysis is presented of the interference between two photon pairs produced in the process of downconversion from two identical crystals, which are then mixed by beam splitters. Because the downconverted photons are entangled with the vacuum, they carry information about the phase of the pump field. As a result the two-photon detection probability is shown to depend on the phase of the pump, even when the resolving time of the detector electronics is far longer than the coherence time of the light.

© 1989 Optical Society of America