Stark位移对混态J-C模型中熵和纠缠的影响

J4 ›› 2012, Vol. 29 ›› Issue (4): 441-447.

Stark位移对混态J-C模型中熵和纠缠的影响

胡要花

洛阳师范学院物理与电子信息学院，河南洛阳 471022

收稿日期:2012-02-07 修回日期:2012-03-12 出版日期:2012-07-28 发布日期:2012-07-01
通讯作者: 胡要花（1979～），女，博士，讲师，主要从事量子光学和量子信息处理方面的研究。 E-mail:huyaohua1@sina.com
基金资助:
国家自然科学基金青年基金(10905028), 河南省科技计划(102300410050)资助项目

Influence of Stark shift on entropy and entanglement in J-C model with mixed states

HU Yaohua

College of Physics and Electronic Information , Luoyang Normal College, Luoyang 471022, China

Received:2012-02-07 Revised:2012-03-12 Published:2012-07-28 Online:2012-07-01

摘要/Abstract

摘要：

考虑一个二能级原子与单模热光场经由双光子过程耦合，采用量子约化熵研究了原子和场的约化熵变化规律，用共生纠缠度(Concurrence)研究了原子与场之间的纠缠演化。借助于数值计算方法，详细分析了在混态J-C模型中，Stark位移和平均光子数对约化熵变和纠缠的影响。结果表明在Stark位移影响下，原子和光场的约化熵变化量均减小。选择适当的原子初态，可以使得原子的约化熵和光场的约化熵发生交换。此外，考虑Stark位移时，原子与光场之间纠缠的最小值增大，原子与光场不再出现退纠缠态。

关键词: 量子光学, 纠缠, 共生纠缠度, 量子约化熵, Stark位移, Jaynes-Cummings模型

Abstract:

A two-level atom coupling with a single-mode thermal ?eld through two-photon processes is considered. It is studied that the reduced entropy change of the atom and the ?eld by using quantum reduced entropy, and entanglement between the atom and field measured by using Concurrence. By mean of numerical computation method, The e?ect of the Stark shift and the mean photon number in the J-C model with mixed states on the reduced entropy change and entanglement is investigated. The results show that reduced entropy changes of the atom and the ?eld decrease under the influence of the Stark shift. When the initial parameters are suitable, the complete exchange between the atomic and field reduced entropy occurs. In addition, the minimum values of the entanglement raise in the presence of the Stark shift, which means that the atom is no longer disentangled from the field.

Key words: quantum optics, entanglement, concurrence, reduced entropy, Stark shift, Jaynes-Cummings model

中图分类号:

O431.2

胡要花. Stark位移对混态J-C模型中熵和纠缠的影响[J]. J4, 2012, 29(4): 441-447.

HU Yaohua. Influence of Stark shift on entropy and entanglement in J-C model with mixed states[J]. J4, 2012, 29(4): 441-447.

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