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arXiv · 0906.3328

Mode expansion and Bragg filtering enable a high-fidelity fiber-based photon-pair source

Alexander Ling·Jun Chen·Jingyun Fan·Alan Migdall
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Abstract

We report the development of a fiber-based single spatial mode source of photon-pairs where the efficiency of extracting photon-pairs is improved over a previous source [18] through the use of fiber-end expansion and Bragg filters. This improvement in efficiency enabled a spectrally bright and pure photon-pair source having a small second-order correlation function (0.03) and a raw spectral brightness of 44,700 pairs/(s nm mW). The source can be configured to generate entangled photon-pairs,characterized via optimal and minimal quantum state tomography, to have a fidelity of 97% and tangle of 92%, without subtracting any background.

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Alexander Ling, Jun Chen, Jingyun Fan, Alan Migdall. 2009-10-05. Mode expansion and Bragg filtering enable a high-fidelity fiber-based photon-pair source. https://doi.org/10.1364/oe.17.021302

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