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arXiv · 1102.1941

Intrinsic Quantum Correlations of Weak Coherent States for Quantum Communication

Yong Meng Sua·Erin Scanlon·Travis Beaulieu·Viktor Bollen·Kim Fook Lee
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Abstract

Intrinsic quantum correlations of weak coherent states are observed between two parties through a novel detection scheme, which can be used as a supplement to the existence decoy-state BB84 and differential phase-shift quantum key distribution (DPS-QKD) protocols. In a proof-of-principle experiment, we generate bi-partite correlations of weak coherent states using weak local oscillator fields in two spatially separated balanced homodyne detections. We employ nonlinearity of post-measurement method to obtain the bi-partite correlations from two single-field interferences at individual homodyne measurement. This scheme is then used to demonstrate bits correlations between two parties over a distance of 10 km through a transmission fiber. We believe that the scheme can add another physical layer of security to these protocols for quantum key distribution.

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Yong Meng Sua, Erin Scanlon, Travis Beaulieu, Viktor Bollen, Kim Fook Lee. 2011-02-09. Intrinsic Quantum Correlations of Weak Coherent States for Quantum Communication. https://arxiv.org/abs/1102.1941

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