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arXiv · 1307.7939

Post-selection free, integrated optical source of non-degenerate, polarization entangled photon pairs

Harald Herrmann·Xu Yang·Abu Thomas·Andreas Poppe·Wolfgang Sohler·Christine Silberhorn
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Abstract

We present an integrated source of polarization entangled photon pairs in the telecom regime, which is based on type II-phasematched parametric down-conversion (PDC) in a Ti-indiffused waveguide in periodically poled lithium niobate. The domain grating -- consisting of an interlaced bi-periodic structure -- is engineered to provide simultaneous phase-matching of two PDC processes, and enables the direct generation of non-degenerate, polarization entangled photon pairs with a brightness of $B=7\times10^3$ pairs/(s mW GHz). The spatial separation of the photon pairs is accomplished by a fiber-optical multiplexer facilitating a high compactness of the overall source. Visibilities exceeding 95% and a violation of the Bell inequality with $S=2.57\pm0.06$ could be demonstrated.

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Harald Herrmann, Xu Yang, Abu Thomas, Andreas Poppe, Wolfgang Sohler, Christine Silberhorn. 2013-07-30. Post-selection free, integrated optical source of non-degenerate, polarization entangled photon pairs. https://doi.org/10.1364/oe.21.027981

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