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arXiv · 1707.00387

Proof-of-principle experimental realization of a qubit-like qudit-based quantum key distribution scheme

Shuang Wang·Zhen-Qiang Yin·H. F. Chau·Wei Chen·Chao Wang·Guang-Can Guo·Zheng-Fu Han
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Abstract

In comparison to qubit-based protocols, qudit-based quantum key distribution (QKD) ones gen- erally allow two cooperative parties to share unconditionally secure keys under a higher channel noise. However, it is very hard to prepare and measure the required quantum states in qudit-based protocols in general. One exception is the recently proposed highly error tolerant qudit-based proto- col known as the Chau15 [1]. Remarkably, the state preparation and measurement in this protocol can be done relatively easily since the required states are phase encoded almost like the diagonal basis states of a qubit. Here we report the first proof-of-principle demonstration of the Chau15 protocol. One highlight of our experiment is that its post-processing is based on practical one-way manner, while the original proposal in Ref. [1] relies on complicated two-way post-processing, which is a great challenge in experiment. In addition, by manipulating time-bin qudit and measurement with a variable delay interferometer, our realization is extensible to qudit with high-dimensionality and confirms the experimental feasibility of the Chau15 protocol.

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Shuang Wang, Zhen-Qiang Yin, H. F. Chau, Wei Chen, Chao Wang, Guang-Can Guo, Zheng-Fu Han. 2017-07-03. Proof-of-principle experimental realization of a qubit-like qudit-based quantum key distribution scheme. https://doi.org/10.1088/2058-9565%2Faaace4

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