Fast multi-copy entanglement purification with linear optics
Cai Chun (蔡春)a c, Zhou Lan (周澜)a b, Sheng Yu-Bo (盛宇波)a c
a Key Laboratory of Broadband Wireless Communication and Sensor Network Technology, Ministry of Education, Nanjing University of Posts and Telecommunications, Nanjing 210003, China;
b College of Mathematics and Physics, Nanjing University of Posts and Telecommunications, Nanjing 210003, China;
c Institute of Signal Processing Transmission, Nanjing University of Posts and Telecommunications, Nanjing 210003, China
We describe an entanglement purification protocol for a polarization Bell state. Different from the previous protocols, it does not require the controlled-not gate, and only uses linear optical elements to complete the task. This protocol requires multi-copy degraded mixed states, which can make this protocol obtain a high fidelity in one purification step. It can also be extended to purify the multi-photon Greenberger-Horne-Zeilinger (GHZ) state. This protocol may be useful in future long-distance communication.
(Quantum computation architectures and implementations)
Fund:
Project supported by the National Natural Science Foundation of China (Grant Nos. 11474168 and 61401222), the Qing Lan Project of Jiangsu Province, China, the STITP Project in Nanjing University of Posts and Telecommunications, the Natural Science Foundation of Jiangsu Province, China (Grant No. BK20151502), the Natural Science Foundation of the Jiangsu Higher Education Institutions (Grant No. 15KJA120002), and the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions, China.
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