Chin. Phys. B ›› 2013, Vol. 22 ›› Issue (4): 40304-040304.doi: 10.1088/1674-1056/22/4/040304

• GENERAL • 上一篇    下一篇

Quantum discord dynamics of two qubits in the single-mode cavities

王晨a, 陈庆虎a b   

  1. a Department of Physics, Zhejiang University, Hangzhou 310027, China;
    b Center for Statistical and Theoretical Condensed Matter Physics, Zhejiang Normal University, Jinhua 321004, China
  • 收稿日期:2012-09-05 修回日期:2012-10-10 出版日期:2013-03-01 发布日期:2013-03-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant No. 11174254) and the National Basic Research Program of China (Grant Nos. 2011CBA00103 and 2009CB929104).

Quantum discord dynamics of two qubits in the single-mode cavities

Wang Chen (王晨)a, Chen Qing-Hu (陈庆虎)a b   

  1. a Department of Physics, Zhejiang University, Hangzhou 310027, China;
    b Center for Statistical and Theoretical Condensed Matter Physics, Zhejiang Normal University, Jinhua 321004, China
  • Received:2012-09-05 Revised:2012-10-10 Online:2013-03-01 Published:2013-03-01
  • Contact: Chen Qing-Hu E-mail:qhchen@zju.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant No. 11174254) and the National Basic Research Program of China (Grant Nos. 2011CBA00103 and 2009CB929104).

摘要: The dynamics of the quantum discord for two identical qubits in both two independent single-mode cavities and a common single-mode cavity are discussed. For the initial Bell state with correlated spins, while the entanglement sudden death can occur, the quantum discord vanishes only at discrete moments in the independent cavities and never vanishes in the common cavity. Interestingly, quantum discord and entanglement show opposite behaviors in the common cavity, unlike in the independent cavities. For the initial Bell state with anti-correlated spins, quantum discord and entanglement behave in the same way for both independent cavities and a common cavity. It is found that the detunings always stabilize the quantum discord.

关键词: quantum information, cavity quantum electrodynamics, entanglement and quantum nonlocality

Abstract: The dynamics of the quantum discord for two identical qubits in both two independent single-mode cavities and a common single-mode cavity are discussed. For the initial Bell state with correlated spins, while the entanglement sudden death can occur, the quantum discord vanishes only at discrete moments in the independent cavities and never vanishes in the common cavity. Interestingly, quantum discord and entanglement show opposite behaviors in the common cavity, unlike in the independent cavities. For the initial Bell state with anti-correlated spins, quantum discord and entanglement behave in the same way for both independent cavities and a common cavity. It is found that the detunings always stabilize the quantum discord.

Key words: quantum information, cavity quantum electrodynamics, entanglement and quantum nonlocality

中图分类号:  (Quantum information)

  • 03.67.-a
42.50.Pq (Cavity quantum electrodynamics; micromasers) 03.65.Ud (Entanglement and quantum nonlocality)