中国物理B ›› 2018, Vol. 27 ›› Issue (11): 110303-110303.doi: 10.1088/1674-1056/27/11/110303

• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇    下一篇

Modulating quantum Fisher information of qubit in dissipative cavity by coupling strength

Danping Lin(林丹萍), Yu Liu(刘禹), Hong-Mei Zou(邹红梅)   

  1. Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha 410081, China
  • 收稿日期:2018-05-30 修回日期:2018-08-31 出版日期:2018-11-05 发布日期:2018-11-05
  • 通讯作者: Hong-Mei Zou E-mail:zhmzc1997@hunnu.edu.cn
  • 基金资助:

    Project supported by the Scientific Research Project of Hunan Provincial Education Department, China (Grant No. 16C0949), Hunan Provincial Innovation Foundation for Postgraduate, China (Grant No. CX2017B177), the National Natural Science Foundation of China (Grant No. 11374096), and the Doctoral Science Foundation of Hunan Normal University, China.

Modulating quantum Fisher information of qubit in dissipative cavity by coupling strength

Danping Lin(林丹萍), Yu Liu(刘禹), Hong-Mei Zou(邹红梅)   

  1. Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha 410081, China
  • Received:2018-05-30 Revised:2018-08-31 Online:2018-11-05 Published:2018-11-05
  • Contact: Hong-Mei Zou E-mail:zhmzc1997@hunnu.edu.cn
  • Supported by:

    Project supported by the Scientific Research Project of Hunan Provincial Education Department, China (Grant No. 16C0949), Hunan Provincial Innovation Foundation for Postgraduate, China (Grant No. CX2017B177), the National Natural Science Foundation of China (Grant No. 11374096), and the Doctoral Science Foundation of Hunan Normal University, China.

摘要:

By using the non-Markovian master equation, we investigate the effect of the cavity and the environment on the quantum Fisher information (QFI) of an atom qubit system in a dissipation cavity. We obtain the formulae of QFI for two different initial states and analyze the effect of the atom-cavity coupling and the cavity-reservoir coupling on the QFI. The results show that the dynamic behavior of the QFI is obviously dependent on the initial atomic states, the atom-cavity coupling, and the cavity-reservoir coupling. The stronger the atom-cavity coupling, the quicker the QFI oscillates, and the slower the QFI decreases. In particular, the QFI will tend to be a stable value rather than zero if the atom-cavity coupling is large enough. On the other hand, the smaller the cavity-reservoir coupling, the stronger the non-Markovian effect, and the slower the QFI decays. In other words, choosing the best parameter can improve the accuracy of the parameter estimation. In addition, the physical explanation of the dynamic behavior of the QFI is given by means of the QFI flow.

关键词: quantum Fisher information, parameter estimation, dissipative cavity

Abstract:

By using the non-Markovian master equation, we investigate the effect of the cavity and the environment on the quantum Fisher information (QFI) of an atom qubit system in a dissipation cavity. We obtain the formulae of QFI for two different initial states and analyze the effect of the atom-cavity coupling and the cavity-reservoir coupling on the QFI. The results show that the dynamic behavior of the QFI is obviously dependent on the initial atomic states, the atom-cavity coupling, and the cavity-reservoir coupling. The stronger the atom-cavity coupling, the quicker the QFI oscillates, and the slower the QFI decreases. In particular, the QFI will tend to be a stable value rather than zero if the atom-cavity coupling is large enough. On the other hand, the smaller the cavity-reservoir coupling, the stronger the non-Markovian effect, and the slower the QFI decays. In other words, choosing the best parameter can improve the accuracy of the parameter estimation. In addition, the physical explanation of the dynamic behavior of the QFI is given by means of the QFI flow.

Key words: quantum Fisher information, parameter estimation, dissipative cavity

中图分类号:  (Decoherence; open systems; quantum statistical methods)

  • 03.65.Yz
03.65.Ta (Foundations of quantum mechanics; measurement theory) 03.67.-a (Quantum information) 42.50.Dv (Quantum state engineering and measurements)