High-probability heralded single-photon source and related method

摘要

A system and method is provided for a source for a heralded single photon comprising a correlated photon-pair generator that provides bursts of multiple photon pairs that may be odd or even in number of pairs, one of each pair having a first but not a second characteristic and the other of each pair having the second but not the first characteristic; a first optical path for photons of pairs having the first characteristic; a second optical path for photons of pairs having the second characteristic; a two-photon absorber in the first optical path that, for each burst of photons, reduces the number of first characteristic photons in the first path to zero or one, depending on whether the number of photon pairs in the burst is even or odd; a photon detector in the second path having a heralding signal output to indicate when the number of photons in the burst is odd; and an optical switch coupled to the output of the second optical path and connected to operate in response to the heralding signal.