Coherence-controlled stationary entanglement between two atoms embedded in a bad cavity injected with squeezed vacuum

被引:1
作者
Liao, Xiang-Ping [1 ]
Fang, Jian-Shu [1 ]
Fang, Mao-Fa [2 ]
机构
[1] Hunan Univ Technol, Coll Sci, Zhuzhou 412007, Hunan, Peoples R China
[2] Hunan Normal Univ, Dept Phys & Informat Sci, Changsha 410081, Hunan, Peoples R China
来源
CENTRAL EUROPEAN JOURNAL OF PHYSICS | 2014年 / 12卷 / 01期
基金
中国国家自然科学基金;
关键词
quantum entanglement; the squeezed vacuum; coherent states; quantum control; SPONTANEOUS EMISSION; QUBITS; RADIATION; SYSTEM; PAIR;
D O I
10.2478/s11534-013-0326-x
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
We investigate the entanglement between two atoms in an overdamped cavity injected with squeezed vacuum when these two atoms are initially prepared in coherent states. It is shown that the stationary entanglement exhibits a strong dependence on the initial state of the two atoms when the spontaneous emission rate of each atom is equal to the collective spontaneous emission rate, corresponding to the case where the two atoms are close together. It is found that the stationary entanglement of two atoms increases with decreasing effective atomic cooperativity parameter. The squeezed vacuum can enhance the entanglement of two atoms when the atoms are initially in coherent states. Valuably, this provides us with a feasible way to manipulate and control the entanglement, by changing the relative phases and the amplitudes of the polarized atoms and by varying the effective atomic cooperativity parameter of the system, even though the cavity is a bad one. When the spontaneous emission rate of each atom is not equal to the collective spontaneous emission rate, the steady-state entanglement of two atoms always maintains the same value, as the amplitudes of the polarized atoms varies. Moreover, the larger the degree of two-photon correlation, the stronger the steady-state entanglement between the atoms.
引用
收藏
页码:9 / 16
页数:8
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