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arXiv · 2305.09404

Realizing fully reference-frame-independent quantum key distribution by exploiting quantum discord

Rong Wang·Chun-Mei Zhang
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Abstract

Reference-frame-independent quantum key distribution was proposed to generate a string of secret keys without a shared reference frame. Based on the Bloch sphere, however, the security analysis in previous methods is only independent on azimuthal angle, while a reference frame is determined by both polar angle and azimuthal angle. Here, we propose a 3 \times 3 matrix whose singular values are independent on both polar angle and azimuthal angle, as well as take advantage of quantum discord, to realize a fully reference-frame-independent quantum key distribution. Furthermore, we numerically show that the performance of our method can reduce to the previous one if the key generation basis is calibrated.

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Rong Wang, Chun-Mei Zhang. 2023-05-16. Realizing fully reference-frame-independent quantum key distribution by exploiting quantum discord. https://doi.org/10.1007/s11432-025-4828-x

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