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Deterministic and Efficient Quantum Cryptography Based on Bell's Theorem

Zeng-Bing Chen·Qiang Zhang·Xiao-Hui Bao·J. Schmiedmayer·Jian-Wei Pan
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Abstract

We propose a novel double-entanglement-based quantum cryptography protocol that is both efficient and deterministic. The proposal uses photon pairs with entanglement both in polarization and in time degrees of freedom; each measurement in which both of the two communicating parties register a photon can establish one and only one perfect correlation and thus deterministically create a key bit. Eavesdropping can be detected by violation of local realism. A variation of the protocol shows a higher security, similarly to the six-state protocol, under individual attacks. Our scheme allows a robust implementation under current technology.

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Zeng-Bing Chen, Qiang Zhang, Xiao-Hui Bao, J. Schmiedmayer, Jian-Wei Pan. 2006-05-05. Deterministic and Efficient Quantum Cryptography Based on Bell's Theorem. https://doi.org/10.1103/physreva.73.050302

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