Information-Disturbance Tradeoff in Estimating the Unknown Three-Qubit GHZ State  

作　　者：张胜利 邹旭波 李科 金晨辉 郭光灿 

机构地区：[1]Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026 [2]Electronic Technology Institute, Information Engineering University, Zhengzhou 450004

出　　处：《Chinese Physics Letters》2007年第6期1456-1459,共4页中国物理快报（英文版）

基　　金：Supported by the National Basic Research Programme of China, the National Natural Science Foundation of China under Grant Nos 10674128 and 60121503, the Knowledge Innovation Project and the Hundreds of Talents Programme of Chinese Academy of Sciences, and the Doctoral Foundation of the Education Ministry of China under Grant No 20060358043.

摘　　要：In a recent paper, Sacchi （Phys. Rev. Lett. 96 （2006） 220502） studied the information-disturbance tradeoff in estimating an unknown two-qubit maximally entangled state. In this study, we explore the tradeoff in estimating 13 an unknown three-qubit GHZ state. The optimal estimation process supplies a fidelity of 13/54 and the tradeoff interpolates smoothly between non-informative measurement and optimal estimation process.In a recent paper, Sacchi （Phys. Rev. Lett. 96 （2006） 220502） studied the information-disturbance tradeoff in estimating an unknown two-qubit maximally entangled state. In this study, we explore the tradeoff in estimating 13 an unknown three-qubit GHZ state. The optimal estimation process supplies a fidelity of 13/54 and the tradeoff interpolates smoothly between non-informative measurement and optimal estimation process.

关 键 词：UNCERTAINTY RELATIONS QUANTUM 

分 类 号：O45[理学—无线电物理]