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arXiv · 0904.1184

Quantum states prepared by realistic entanglement swapping

Artur Scherer·Regina B. Howard·Barry C. Sanders·Wolfgang Tittel
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Abstract

Entanglement swapping between photon pairs is a fundamental building block in schemes using quantum relays or quantum repeaters to overcome the range limits of long-distance quantum key distribution. We develop a closed-form solution for the actual quantum states prepared by realistic entanglement swapping, which takes into account experimental deficiencies due to inefficient detectors, detector dark counts, and multiphoton-pair contributions of parametric down-conversion sources. We investigate how the entanglement present in the final state of the remaining modes is affected by the real-world imperfections. To test the predictions of our theory, comparison with previously published experimental entanglement swapping is provided.

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Artur Scherer, Regina B. Howard, Barry C. Sanders, Wolfgang Tittel. 2009-04-07. Quantum states prepared by realistic entanglement swapping. https://doi.org/10.1103/physreva.80.062310

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