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arXiv · 2408.07552

Quantum key distribution based on mid-infrared and telecom band two-color entanglement source

Wu-Zhen Li·Chun Zhou·Yang Wang·Li Chen·Ren-Hui Chen·Zhao-Qi-Zhi Han·Ming-Yuan Gao·Xiao-Hua Wang·Di-Yuan Zheng·Meng-Yu Xie·Yin-Hai Li·Zhi-Yuan Zhou·Wan-Su Bao·Bao-Sen Shi
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Abstract

Due to the high noise caused by solar background radiation, the existing satellite-based free-space quantum key distribution (QKD) experiments are mainly carried out at night, hindering the establishment of a practical all-day real-time global-scale quantum network. Given that the 3-5 {\mu}m mid-infrared (MIR) band has extremely low solar background radiation and strong scattering resistance, it is one of the ideal bands for free-space quantum communication. Here, firstly, we report on the preparation of a high-quality MIR (3370 nm) and telecom band (1555 nm) two-color polarization-entangled photon source, then we use this source to realize a principle QKD based on free-space and fiber hybrid channels in a laboratory. The theoretical analysis clearly shows that a long-distance QKD over 500 km of free-space and 96 km of fiber hybrid channels can be reached simultaneously. This work represents a significant step toward developing all-day global-scale quantum communication networks.

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Wu-Zhen Li, Chun Zhou, Yang Wang, Li Chen, Ren-Hui Chen, Zhao-Qi-Zhi Han, Ming-Yuan Gao, Xiao-Hua Wang, Di-Yuan Zheng, Meng-Yu Xie, Yin-Hai Li, Zhi-Yuan Zhou, Wan-Su Bao, Bao-Sen Shi. 2024-08-14. Quantum key distribution based on mid-infrared and telecom band two-color entanglement source. https://arxiv.org/abs/2408.07552

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