中国物理B ›› 2016, Vol. 25 ›› Issue (12): 120302-120302.doi: 10.1088/1674-1056/25/12/120302

• GENERAL • 上一篇    下一篇

Quantum process discrimination with information from environment

Yuan-Mei Wang(王元美), Jun-Gang Li(李军刚), Jian Zou(邹健), Bao-Ming Xu(徐宝明)   

  1. 1. School of Physics, Beijing Institute of Technology, Beijing 100081, China;
    2. School of Physics, Qufu Normal University, Qufu 273165, China
  • 收稿日期:2016-05-14 修回日期:2016-07-21 出版日期:2016-12-05 发布日期:2016-12-05
  • 通讯作者: Jun-Gang Li E-mail:jungl@bit.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11274043, 11375025, and 11005008).

Quantum process discrimination with information from environment

Yuan-Mei Wang(王元美)1, Jun-Gang Li(李军刚)1, Jian Zou(邹健)1, Bao-Ming Xu(徐宝明)2   

  1. 1. School of Physics, Beijing Institute of Technology, Beijing 100081, China;
    2. School of Physics, Qufu Normal University, Qufu 273165, China
  • Received:2016-05-14 Revised:2016-07-21 Online:2016-12-05 Published:2016-12-05
  • Contact: Jun-Gang Li E-mail:jungl@bit.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11274043, 11375025, and 11005008).

摘要:

In quantum metrology we usually extract information from the reduced probe system but ignore the information lost inevitably into the environment. However, K. Mølmer[Phys. Rev. Lett. 114, 040401 (2015)] showed that the information lost into the environment has an important effect on improving the successful probability of quantum process discrimination. Here we reconsider the model of a driven atom coupled to an environment and distinguish which of two candidate Hamiltonians governs the dynamics of the whole system. We mainly discuss two measurement methods, one of which obtains only the information from the reduced atom state and the other obtains the information from both the atom and its environment. Interestingly, for the two methods the optimal initial states of the atom, used to improve the successful probability of the process discrimination, are different. By comparing the two methods we find that the partial information from the environment is very useful for the discriminations.

关键词: quantum process discrimination, information in the environment, overlap

Abstract:

In quantum metrology we usually extract information from the reduced probe system but ignore the information lost inevitably into the environment. However, K. Mølmer[Phys. Rev. Lett. 114, 040401 (2015)] showed that the information lost into the environment has an important effect on improving the successful probability of quantum process discrimination. Here we reconsider the model of a driven atom coupled to an environment and distinguish which of two candidate Hamiltonians governs the dynamics of the whole system. We mainly discuss two measurement methods, one of which obtains only the information from the reduced atom state and the other obtains the information from both the atom and its environment. Interestingly, for the two methods the optimal initial states of the atom, used to improve the successful probability of the process discrimination, are different. By comparing the two methods we find that the partial information from the environment is very useful for the discriminations.

Key words: quantum process discrimination, information in the environment, overlap

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

  • 03.65.Yz
02.50.Tt (Inference methods) 03.67.-a (Quantum information) 42.50.Dv (Quantum state engineering and measurements)