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arXiv · 0809.0071

Tailored photon-pair generation in optical fibers

Offir Cohen·Jeff S. Lundeen·Brian J. Smith·Graciana Puentes·Peter J. Mosley·Ian A. Walmsley
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Abstract

We experimentally control the spectral structure of photon pairs created via spontaneous four-wave mixing in microstructured fibers. By fabricating fibers with designed dispersion, one can manipulate the photons' wavelengths, joint spectrum, and, thus, entanglement. As an example, we produce photon-pairs with no spectral correlations, allowing direct heralding of single photons in pure-state wave packets without filtering. We achieve an experimental purity of $85.9\pm1.6%$, while theoretical analysis and preliminary tests suggest 94.5% purity is possible with a much longer fiber.

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Offir Cohen, Jeff S. Lundeen, Brian J. Smith, Graciana Puentes, Peter J. Mosley, Ian A. Walmsley. 2009-04-14. Tailored photon-pair generation in optical fibers. https://doi.org/10.1103/physrevlett.102.123603

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