摘要
We employ quantum state and process tomography with time-bin qubits to benchmark a city-wide metropolitan quantum communication system.Over this network,we implement real-time feedback control systems for stabilizing the phase of the time-bin qubits and obtain a 99.3%quantum process fidelity to the ideal channel,indicating the high quality of the whole quantum communication system.This allows us to implement a field trial of high-performance quantum key distribution using coherent one way protocol with an average quantum bit error rate and visibility of 0.25%and 99.2%during 12 h over 61 km.Our results pave the way for the high-performance quantum network with metropolitan fibers.
作者
张佩瑜
陆亮亮
渠方超
蒋新贺
郑晓冬
陆延青
祝世宁
马小松
Peiyu Zhang;Liangliang Lu;Fangchao Qu;Xinhe Jiang;Xiaodong Zheng;Yanqing Lu;Shining Zhu;Xiao-Song Ma(National Laboratory of Solid-state Microstructures,School of Physics,College of Engineering and Applied Sciences,Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China)
基金
supported by the National Key Research and Development Program of China(Nos.2017YFA0303704 and 2019YFA0308704)
the National Natural Science Foundation of China(Nos.11674170,11690032,and 11804153)
NSFC-BRICS(No.61961146001)
the Natural Science Foundation of Jiangsu Province(No.BK20170010)
the Leading-edge Technology Program of Jiangsu Natural Science Foundation(BK20192001)
the program for Innovative Talents and Entrepreneur in Jiangsu
the Fundamental Research Funds for the Central Universities。