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Deterministic and Highly Efficient Quantum Cryptography with Entangled Photon Pairs

Zhi Zhao·Tao Yang·Zeng-Bing Chen·Jiangfeng Du·Jian-Wei Pan
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Abstract

We present a protocol for deterministic and highly efficient quantum cryptography with entangled photon pairs in a 4x4-dimentional Hilbert space. Two communicating parties, Alice and Bob first share a both polarization- and path-entangled photon pair, and then each performs a complete Bell-state measurement on their own photon in one of two complementary Bell-state bases. It is demonstrated that each measurement in which both Alice and Bob register a photon can build certain perfect correlation and generate 1.5 key bits on average. The security of our protocol is guaranteed by the non-cloning theorem.

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Zhi Zhao, Tao Yang, Zeng-Bing Chen, Jiangfeng Du, Jian-Wei Pan. 2003-09-11. Deterministic and Highly Efficient Quantum Cryptography with Entangled Photon Pairs. https://arxiv.org/abs/quant-ph/0211098

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