经典激光场驱动下的两量子比特纠缠动力学

J4 ›› 2010, Vol. 27 ›› Issue (5): 558-564.

经典激光场驱动下的两量子比特纠缠动力学

肖庆生¹, 钟阳万¹, 刘燕勇²

1 江西理工大学信息工程学院，江西赣州 341000； 2 江西理工大学理学院，江西赣州，341000

收稿日期:2010-04-07 修回日期:2010-05-24 出版日期:2010-09-28 发布日期:2010-08-31
通讯作者: 肖庆生（1980—），男，江西兴国人，江西理工大学信息工程学院教师，研究方向为光学。 E-mail:photonxqs@126.com

Entanglement dynamics of two qubits driven by classical laser field

XIAO Qingsheng¹，ZHONG Yangwan¹, LIU Yanyong²

1 School of Information Engineering, Jiangxi University of Science and Technology, Ganzhou 341000， China；
2 School of Science, Jiangxi University of Science and Technology, Ganzhou 341000 , China

Received:2010-04-07 Revised:2010-05-24 Published:2010-09-28 Online:2010-08-31

摘要/Abstract

摘要：

利用超算符的方法研究了在经典激光场驱动下，分别囚禁在两个独立腔中的两个二能级原子的纠缠动力学。结果表明：两原子纠缠与腔场相干态的初始值无关，并且在腔场耗散比较小的时候，经典光驱动场会加速两原子的纠缠突然死亡，但是在腔场耗散比较大的时候，经典驱动场可以保护原子纠缠免于突然死亡。这说明即便在“坏”腔中，我们也可以通过加经典驱动场来避免原子纠缠突然死亡。

关键词: 经典驱动场, 纠缠动力学, 共生纠缠度, 纠缠突然死亡

Abstract:

The entanglement dynamics of two two-level atoms, respectively trapped in two independent dissipative single-mode cavities and strongly driven by the classical fields was investigated through solving the master equation analytically by using super operator method. It is found that the entanglement is not related to the initial value of the cavity coherent states. The driving field enhances the entanglement sudden death for small dissipation of the cavity, while it protects the entanglement from sudden death for large dissipation in the presence of strong driving field. These results show that even in the bad cavity (with large decay rate), the entanglement could be free from sudden death with the assistance of classical driving field.

Key words: classical driving field, entanglement dynamics, concurrence, entanglement sudden death

肖庆生钟阳万刘燕勇. 经典激光场驱动下的两量子比特纠缠动力学[J]. J4, 2010, 27(5): 558-564.

XIAO Qingsheng ZHONG Yangwan LIU Yanyong. Entanglement dynamics of two qubits driven by classical laser field[J]. J4, 2010, 27(5): 558-564.

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