Experimental measurement-device-independent quantum digital signatures over a metropolitan network
Hua‐Lei Yin, Wei-Long Wang, Yan-Lin Tang, Qi Zhao, Hui Liu, Xiang-Xiang Sun, Wei-Jun Zhang, Hao Li, Ittoop Vergheese Puthoor, Lixing You, Erika Andersson, Zhen Wang, Yang Liu, Xiao Qiang Jiang, Xiongfeng Ma, Qiang Zhang, Marcos Curty, Teng‐Yun Chen, Jian-Wei Pan · Physical Review A · 2017
Quantum digital signatures (QDSs) provide a means for signing electronic communications with information-theoretic security. However, all previous demonstrations of quantum digital signatures assume trusted measurement devices. This renders them vulnerable against detector side-channel attacks, just like quantum key distribution. Here we exploit a measurement-device-independent (MDI) quantum network, over a metropolitan area, to perform a field test of a three-party MDI QDS scheme that is secure against any detector side-channel attack. In so doing, we are able to successfully sign a binary message with a security level of about ${10}^{\ensuremath{-}7}$. Remarkably, our work demonstrates the feasibility of MDI QDSs for practical applications.