Rotation of Bloch sphere induced by Lamb shift in open two-level systems  

作　　者：王国友 唐宁 刘颖 曾浩生 

机构地区：[1]Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education,Hunan Normal University [2]Department of Physics, Hunan Normal University

出　　处：《Chinese Physics B》2015年第5期198-203,共6页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.11275064 and 11075050);the Specialized Research Fund for the Doctoral Program of Higher Education,China(Grant No.20124306110003);the Program for Changjiang Scholars and Innovative Research Team in University,China(Grant No.IRT0964);the Construct Program of the National Key Discipline,China

摘　　要：From a quite general form of the Lindblad-like master equation of open two-level systems （qubits）, we study the effect of Lamb shift on the non-Markovian dynamics. We find that the Lamb shift can induce a non-uniform rotation of the Bloch sphere, but that it does not affect the non-Markovianity of the open system dynamics. We determine the optimal initial-state pairs that maximize the backflow of information for the considered master equation and find an interesting phenomenon-the sudden change of the non-Markovianity. We relate the dynamics to the evolution of the Bloch sphere to help us comprehend the obtained results.From a quite general form of the Lindblad-like master equation of open two-level systems （qubits）, we study the effect of Lamb shift on the non-Markovian dynamics. We find that the Lamb shift can induce a non-uniform rotation of the Bloch sphere, but that it does not affect the non-Markovianity of the open system dynamics. We determine the optimal initial-state pairs that maximize the backflow of information for the considered master equation and find an interesting phenomenon-the sudden change of the non-Markovianity. We relate the dynamics to the evolution of the Bloch sphere to help us comprehend the obtained results.

关 键 词：non-Markovianity Lamb shift Bloch sphere 

分 类 号：O413.1[理学—理论物理]