Observation of Spatial Quantum Beating with Separated Photodetectors 论文

摘要

When signal and idler photons produced in the process of parametric down-conversion are mixed together, and directed to two photodetectors that respond to nonoverlapping optical frequencies centered at ${\ensuremath{\omega}}_{1}$ and ${\ensuremath{\omega}}_{2}$, it is found that the joint probability of two-photon detection exhibits a modulation of the form $cos({\ensuremath{\omega}}_{1}\ensuremath{-}{\ensuremath{\omega}}_{2})\ensuremath{\tau}$, where $c\ensuremath{\tau}$ is the path difference. The experimental results are well described by a simple quantum-mechanical analysis.