Dynamics of quantum Fisher information in a two-level system coupled to multiple bosonic reservoirs  

作　　者：王国友 郭有能 曾可 

机构地区：[1]College of Science, Hunan University of Technology [2]Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, and Department of Physics,Hunan Normal University [3]Department of Electronic and Communication Engineering, Changsha University

出　　处：《Chinese Physics B》2015年第11期255-259,共5页中国物理B（英文版）

基　　金：supported by the Hunan Provincial Innovation Foundation for Postgraduate,China(Grant No.CX2014B194);the Scientific Research Foundation of Hunan Provincial Education Department,China(Grant No.13C039)

摘　　要：We consider the optimal parameter estimation for a two-level system coupled to multiple bosonic reservoirs. By using quantum Fisher information （QFI）, we investigate the effect of the Markovian reservoirs＇ number N on QFI in both weak and strong coupling regimes for a two-level system surrounded by N zero-temperature reservoirs of field modes initially in the vacua. The results show that the dynamics of QFI non-monotonically decays to zero with revival oscillations at some time in the weak coupling regime depending on the reservoirs＇ parameters. Furthermore, we also present the relations between the QFI flow, the flows of energy and information, and the sign of the decay rate to gain insight into the physical processes characterizing the dynamics.We consider the optimal parameter estimation for a two-level system coupled to multiple bosonic reservoirs. By using quantum Fisher information （QFI）, we investigate the effect of the Markovian reservoirs＇ number N on QFI in both weak and strong coupling regimes for a two-level system surrounded by N zero-temperature reservoirs of field modes initially in the vacua. The results show that the dynamics of QFI non-monotonically decays to zero with revival oscillations at some time in the weak coupling regime depending on the reservoirs＇ parameters. Furthermore, we also present the relations between the QFI flow, the flows of energy and information, and the sign of the decay rate to gain insight into the physical processes characterizing the dynamics.

关 键 词：quantum Fisher information parameter estimation decay rate 

分 类 号：O413[理学—理论物理] O211.62[理学—物理]