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arXiv · 1309.2457

High efficiency coupling of photon pairs in practice

T. Guerreiro·A. Martin·B. Sanguinetti·N. Bruno·H. Zbinden·R. T. Thew
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Abstract

Multi-photon and quantum communication experiments such as loophole-free Bell tests and device independent quantum key distribution require entangled photon sources which display high coupling efficiency. In this paper we put forward a simple quantum theoretical model which allows the experimenter to design a source with high pair coupling efficiency. In particular we apply this approach to a situation where high coupling has not been previously obtained: we demonstrate a symmetric coupling efficiency of more than 80% in a highly frequency non-degenerate configuration. Furthermore, we demonstrate this technique in a broad range of configurations, i.e. in continuous wave and pulsed pump regimes, and for different nonlinear crystals.

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T. Guerreiro, A. Martin, B. Sanguinetti, N. Bruno, H. Zbinden, R. T. Thew. 2013-09-10. High efficiency coupling of photon pairs in practice. https://doi.org/10.1364/oe.21.027641

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