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Practical quantum repeaters with linear optics and double-photon guns

Pieter Kok·Colin P. Williams·Jonathan P. Dowling
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Abstract

We show how to create practical, efficient, quantum repeaters, employing double-photon guns, for long-distance optical quantum communication. The guns create polarization-entangled photon pairs on demand. One such source might be a semiconducter quantum dot, which has the distinct advantage over parametric down-conversion that the probability of creating a photon pair is close to one, while the probability of creating multiple pairs vanishes. The swapping and purifying components are implemented by polarizing beam splitters and probabilistic optical CNOT gates.

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Pieter Kok, Colin P. Williams, Jonathan P. Dowling. 2002-03-27. Practical quantum repeaters with linear optics and double-photon guns. https://doi.org/10.1103/physreva.68.022301

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