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arXiv · 2403.10294

Experimental demonstration of improved reference-frame-independent quantum key distribution over 175km

Zhiyu Tian·Ziran Xie·Rong Wang·Chunmei Zhang·Shihai Sun
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Abstract

Reference-frame-independent (RFI) quantum key distribution (QKD) presents promising advantages, especially for mobile-platform-based implementations, as it eliminates the need for active reference frame calibration. While RFI-QKD has been explored in various studies, limitations in key rate and distance persist due to finite data collection. In this study, we experimentally demonstrate an improved RFI-QKD protocol proposed by Zhu \textit{et al.} [Opt. Lett. 47, 4219 (2022)], featuring a statistical quantity for bounding information leaked to Eve that exhibits more insensitivity to statistical fluctuations and more robustness to variations in the reference frame. Taking into account finite-size considerations and potential general attacks, RFI-QKD is implemented over a distance of 175 \si{\kilo\meter} in this work. We believe that our study extends the communication distance achievable by RFI-QKD, thereby constituting a notable advancement for its practical application.

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Zhiyu Tian, Ziran Xie, Rong Wang, Chunmei Zhang, Shihai Sun. 2024-03-15. Experimental demonstration of improved reference-frame-independent quantum key distribution over 175km. https://doi.org/10.1364/oe.522384

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