中国物理B ›› 2014, Vol. 23 ›› Issue (2): 20304-020304.doi: 10.1088/1674-1056/23/2/020304

• GENERAL • 上一篇    下一篇

Preserving entanglement and the fidelity of three-qubit quantum states undergoing decoherence using weak measurement

廖湘萍a, 方卯发b, 方见树a, 朱钱泉a   

  1. a College of Science, Hunan University of Technology, Zhuzhou 412008, China;
    b College of Physics and Information Science, Hunan Normal University, Changsha 410081, China
  • 收稿日期:2013-04-16 修回日期:2013-07-17 出版日期:2013-12-12 发布日期:2013-12-12
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11074072), the Natural Science Foundation of Hunan Province of China (Grant No. 10JJ3088), the Major Program for the Research Foundation of the Education Bureau of Hunan Province of China (Grant No. 10A026), and the Program for the Research Foundation of the Education Bureau of Hunan Province of China (Grant No. 10C0658).

Preserving entanglement and the fidelity of three-qubit quantum states undergoing decoherence using weak measurement

Liao Xiang-Ping (廖湘萍)a, Fang Mao-Fa (方卯发)b, Fang Jian-Shu (方见树)a, Zhu Qian-Quan (朱钱泉)a   

  1. a College of Science, Hunan University of Technology, Zhuzhou 412008, China;
    b College of Physics and Information Science, Hunan Normal University, Changsha 410081, China
  • Received:2013-04-16 Revised:2013-07-17 Online:2013-12-12 Published:2013-12-12
  • Contact: Liao Xiang-Ping, Fang Jian-Shu E-mail:Liaoxp1@126.com;fjs289@163.com
  • About author:03.65.Ud; 42.50.Dv; 03.67.Lx; 03.67.Hk
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11074072), the Natural Science Foundation of Hunan Province of China (Grant No. 10JJ3088), the Major Program for the Research Foundation of the Education Bureau of Hunan Province of China (Grant No. 10A026), and the Program for the Research Foundation of the Education Bureau of Hunan Province of China (Grant No. 10C0658).

摘要: We demonstrate a method to preserve entanglement and improve fidelity of three-qubit quantum states undergoing amplitude-damping decoherence using weak measurement and quantum measurement reversal. It is shown that we are able to enhance entanglement to the greatest extent, and to circumvent entanglement sudden death by increasing the weak measurement strength both for the GHZ state and the W state. The weak measurement technique can also enhance the fidelity to the quantum region and even close to 1 for the whole range of the decoherence parameter in both of the two cases. In addition, the W state can maintain more fidelity than the GHZ state in the protection protocol. However, the GHZ state has a higher success probability than the W state.

关键词: entanglement protection, quantum fidelity, weak measurement

Abstract: We demonstrate a method to preserve entanglement and improve fidelity of three-qubit quantum states undergoing amplitude-damping decoherence using weak measurement and quantum measurement reversal. It is shown that we are able to enhance entanglement to the greatest extent, and to circumvent entanglement sudden death by increasing the weak measurement strength both for the GHZ state and the W state. The weak measurement technique can also enhance the fidelity to the quantum region and even close to 1 for the whole range of the decoherence parameter in both of the two cases. In addition, the W state can maintain more fidelity than the GHZ state in the protection protocol. However, the GHZ state has a higher success probability than the W state.

Key words: entanglement protection, quantum fidelity, weak measurement

中图分类号:  (Entanglement and quantum nonlocality)

  • 03.65.Ud
42.50.Dv (Quantum state engineering and measurements) 03.67.Lx (Quantum computation architectures and implementations) 03.67.Hk (Quantum communication)