Characterizing Quantum Correlations in Arbitrary-Dimensional Bipartite Systems Using Hurwitz＇s Theory  

作　　者：LI Hui 

机构地区：[1]State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China [2]Tsinghua National Laboratory for Information Science and Technology, Beijing 100084, China [3]Collaborative Innovation Center of Quantum Matter, Beijing 100084, China

出　　处：《Communications in Theoretical Physics》2014年第3期273-280,共8页理论物理通讯（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant Nos. 10874098 and 11175094 and the National Basic Research Program of China under Grant Nos. 2009CB929402 and 2011CB9216002, GLL is a Member of Center of Atomic and Molecular Nanosciences, Tsinghua University

摘　　要：Quantum correlations play vital roles in the quantum features in quantum information processing tasks. Among the measures of quantum correlations, quantum discord （QD） and entanglement of formation （EOF） axe two significant ones. Recent research has shown that there exists a relation between QD and EOF, which makes QD more significant in quantum information theory. However, until now, there exists no general method of chaxaeterizing quantum discord in high-dimensional quantum systems. In this paper, we have proposed a general method for calculating quantum discord in axbitraxy-dimensionM bipaxtite quantum systems in terms of Hurwitz＇s theory. Applications including the Werner state, the spin-1 XXZ model thermal equilibrium state, the Horodecki state, and the separable-bound-free entanglement state are investigated. We present the method of obtaining the EOF of axbitraxy-dimensional bipaxtite quantum states via purification, and the relations.hip between QD and EOF.

关 键 词：quantum correlation quantum discord entanglement of formation 

分 类 号：O413.1[理学—理论物理] O156.4[理学—物理]