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arXiv · 1711.05978

Continuous-variable measurement-device-independent quantum key distribution with photon subtraction

Hong-Xin Ma·Peng Huang·Dong-Yun Bai·Shi-Yu Wang·Wan-Su Bao·Gui-Hua Zeng
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Abstract

It has been found that non-Gaussian operations can be applied to increase and distill entanglement between Gaussian entangled states. We show the successful use of the non-Gaussian operation, in particular, photon subtraction operation, on the continuous-variable measurement-device-independent quantum key distribution (CV-MDI-QKD) protocol. The proposed method can be implemented based on existing technologies. Security analysis shows that the photon subtraction operation can remarkably increase the maximal transmission distance of the CV-MDI-QKD protocol, which precisely make up for the shortcoming of the original CV-MDI-QKD protocol, and 1-photon subtraction operation has the best performance. Moreover, the proposed protocol provides a feasible method for the experimental implementation of the CV-MDI-QKD protocol.

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Hong-Xin Ma, Peng Huang, Dong-Yun Bai, Shi-Yu Wang, Wan-Su Bao, Gui-Hua Zeng. 2017-11-16. Continuous-variable measurement-device-independent quantum key distribution with photon subtraction. https://doi.org/10.1103/physreva.97.042329

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