Photon-number state on-demand source by cavity parametric downconversion

The authors propose a realizable scheme for an arbitrary photon-number state on-demand source based on parametric downconversion in a doubly resonant photonic cavity. The signal-wavelength resonance serves as storage for signal photons and the idler-wavelength resonance generates time separation between exiting idler photons, enabling photon-number-resolving detection. The counting of idler photons indicates the desired signal photon-number state, which can be released from the cavity on demand. They analyze the statistics of photon-number states generation and estimate the maximal repetition rates. Performance of the monolithic cavity for signal-storage and idler time spacing is limited, however, by external devices, namely, the long recovery time of existing single-photon detectors. © 2006 American Institute of Physics. DOI: 10.1063/1.2364877