Open AccessAn average photon number measurement scheme based on balanced homodyne detection
Author(s) -
西南通信研究所,
保密通信重点实验室
Publication year - 2021
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.70.20211216
Subject(s) - quantum key distribution , physics , direct conversion receiver , photon , homodyne detection , detector , photon counting , distribution (mathematics) , local oscillator , statistics , algorithm , computer science , mathematics , quantum mechanics , optics , mathematical analysis , phase noise
Quantum key distribution (QKD) has become an alternative technology defensing the security threat resulting from quantum computing. Owing to its superiority in coexistence with optical infrastructures and cost-effective, continuous variable QKD (CV-QKD) is widely studied and developed towards the practical application stage. The standardized measurement of critical parameters of the system should be studied urgently. In this work we propose a scheme based on balanced homodyne detection with phase-randomized local oscillator to realize the average photon number measurement. By controlling local oscillator phase positively, which obeys \begin{document}$ [0,\mathrm{ }2\mathrm{\pi }] $\end{document}uniform distribution, a linear relationship between average photon numbers and the variance of detector output can be obtained in simulation and experiment. With high-accuracy (0.1) photons/pulse and large range 23 dB, this average photon number measurement scheme provides a great reference to evaluating the critical parameters of CV-QKD system in the practical process.