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Functional Quantum Nodes for Entanglement Distribution over Scalable Quantum Networks

Chin-Wen Chou·Julien Laurat·Hui Deng·Kyung Soo Choi·Hugues de Riedmatten·Daniel Felinto·H. Jeff Kimble
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Abstract

We demonstrate entanglement distribution between two remote quantum nodes located 3 meters apart. This distribution involves the asynchronous preparation of two pairs of atomic memories and the coherent mapping of stored atomic states into light fields in an effective state of near maximum polarization entanglement. Entanglement is verified by way of the measured violation of a Bell inequality, and can be used for communication protocols such as quantum cryptography. The demonstrated quantum nodes and channels can be used as segments of a quantum repeater, providing an essential tool for robust long-distance quantum communication.

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Chin-Wen Chou, Julien Laurat, Hui Deng, Kyung Soo Choi, Hugues de Riedmatten, Daniel Felinto, H. Jeff Kimble. 2007-02-06. Functional Quantum Nodes for Entanglement Distribution over Scalable Quantum Networks. https://doi.org/10.1126/science.1140300

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