Filtering of two-photon quantum correlations by optical cavities: cancellation of dispersive effects

Abstract

The spectral filtering of a field with strong quantum correlations is studied. The changes in the correlation characteristics of a field, produced by a down converter, passing through a strongly dispersive element like a Fabry-Perot cavity, are calculated. In the special case when the central frequency of the idler and signal photons coincides with the resonance frequency of the cavity, there is a cancellation of the dispersive effects of the cavity. Detailed numerical results for the two-photon joint counting rate are presented. The effects of the absorption in the medium on the two-photon correlations are also discussed.