| 摘要 |
A first and second heralded photon sources 4a,b each convert pump light photons 6a and 6b into first and second correlated photon pairs 8 and 14, each comprising one signal photon 8a, 14a and one idler photon 8b, 14b. One photon from the first and one from the second source are output into optical path 20. The signal or idler photon from the first source controls the conversion of pump photons in the second source. Detectors and control devices 10 are used for that purpose. Control may result in: stopping the conversion process in the second photon source; increasing the likelihood that the second source emits photons, e.g. where n number of output photons are required; tuning the wavelengths of the second photon pair. A series of concatenated photon pair sources is used for on-demand single photon source comprising spontaneous four wave mixing or spontaneous parametric down-conversion (SFWM, SPDC). |
