Physical Review Letters

Cavity Enhanced Spontaneous Parametric Down-Conversion for the Prolongation of Correlation Time between Conjugate Photons

Z. Y. Ou, Y. J. Lu

Published Sep 27, 1999• 264 citations

Abstract

By resonating both fields of the spontaneous parametric down-conversion with an optical cavity, the bandwidth of the fields is reduced to a level that can be resolved by photodetectors. This enables us to directly measure the distribution of the time intervals between the two down-converted photons. The correlation time is found inversely proportional to the down-conversion bandwidth. In the meantime, the signal levels of the fields are greatly enhanced by the resonance. Such a two-photon source will find wide application in quantum information processing.

DOI: 10.1103/physrevlett.83.2556

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