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arXiv · 1905.09197

Demonstration of a 6 State-4 State Reference Frame Independent channel for Quantum Key Distribution

Ramy Tannous·Zhangdong Ye·Jeongwan Jin·Katanya B. Kuntz·Norbert Lütkenhaus·Thomas Jennewein
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Abstract

We study a novel protocol for reference frame independent (RFI) quantum key distribution (QKD) using six states for Alice and four states for Bob, while previous RFI protocols require a six state analyzer for Bob. Our protocol can generate a secure key for any possible phase of the entangled state, provided the variation is small compared to the measurement rate, shown by our numerical key rate analysis. We perform a proof-of-principle experiment using polarization entangled photon pairs. In the presence of a varying rotational phase, we obtain a consistently low error rate of less than $4\%$ indicating the feasibility of this protocol for QKD. Our protocol is hence beneficial but not limited to applications in satellite or mobile free-space QKD, where a communication node must limit resources and restrict the number of measured states to four instead of six.

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Ramy Tannous, Zhangdong Ye, Jeongwan Jin, Katanya B. Kuntz, Norbert Lütkenhaus, Thomas Jennewein. 2019-11-19. Demonstration of a 6 State-4 State Reference Frame Independent channel for Quantum Key Distribution. https://doi.org/10.1063/1.5125700

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