外磁场下两量子比特海森堡XXZ模型中量子关联和热纠缠的研究

J4 ›› 2012, Vol. 29 ›› Issue (2): 185-191.

外磁场下两量子比特海森堡XXZ模型中量子关联和热纠缠的研究

许琳, 夏云杰

山东省激光偏光与信息技术重点实验室，曲阜师范大学物理工程学院，山东曲阜 273165

收稿日期:2011-03-29 修回日期:2011-05-11 出版日期:2012-03-28 发布日期:2012-02-28
通讯作者: 夏云杰(1963-)山东济宁人，教授，主要从事量子光学与量子信息研究。 E-mail:yjxia@mail.qfnu.edu.cn
作者简介:许琳(1985-)山东潍坊人，研究生，主要从事量子光学与量子信息研究。E-mail：qflq2004@163.com
基金资助:
国家自然科学基金项目(10947006)；高等学校博士学科点专项科研基金(20093705110001）

Quantum correlations and thermal entanglement in a two-qubit Heisenberg XXZ model with external magnetic fields

XU Lin, XIA Yun-jie

Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu 273165, China

Received:2011-03-29 Revised:2011-05-11 Published:2012-03-28 Online:2012-02-28

摘要/Abstract

摘要：

通过在两量子位上分别施加独立可控的外磁场( )和( ），以及改变耦合参数、磁场强度、磁场不均匀度和系统的温度，探讨了两量子比特XXZ模型中量子关联的变化行为，并在相同参数下与热纠缠做了比较。结果表明：量子关联存在的参数范围比热纠缠更广；而且在一定的参数范围内，量子关联和热纠缠的变化展示出不同的行为。

关键词: 量子光学, 量子关联, 热纠缠, quantum discord, 海森堡XXZ模型

Abstract:

The quantum correlation of a two-qubit Heisenberg XXZ model has been investigated through applying two independent and controllable magnetic fields ( ) and ( ) on the two qubits respectively and changing the coupling parameter , magnetic field , inhomogeneous magnetic field and temperature . The behavior of quantum correlation and that of thermal entanglement under one and the same parameter is compared. The results show that quantum correlation can exist for a wider parameter range than thermal entanglement. In addition, for a certain region of parameter, quantum correlation and thermal entanglement exhibit completely different behaviors.

Key words: quantum optics, quantum correlation, thermal entanglement, quantum discord, Heisenberg XXZ model

中图分类号:

O431.2

许琳夏云杰. 外磁场下两量子比特海森堡XXZ模型中量子关联和热纠缠的研究[J]. J4, 2012, 29(2): 185-191.

XU Lin, XIA Yun-jie. Quantum correlations and thermal entanglement in a two-qubit Heisenberg XXZ model with external magnetic fields[J]. J4, 2012, 29(2): 185-191.

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