摘要
在压缩真空库中,研究了原子与场的相互作用下二比特体系的量子discord和量子纠缠的动力学行为.重点分析了原子的初始态系数和压缩真空库的压缩系数对量子纠缠和量子discord的影响.通过数值分析我们得到,随着原子的初始态系数和压缩真空库的压缩系数值的增加,量子纠缠和量子discord都会减小,但量子纠缠比量子discord减小的更快一些.最后研究了在原子的初始态系数和压缩真空库的压缩系数的值相同的情况下,量子discord比量子纠缠存在的时间更长些.
In the squeezed vacuum reservoir,we study the dynamics behavior of quantum discord and quantum entanglement in two-qubit system interaction of the field-atom. We analyze the influences of the atomic initial state parameter and the squeeze parameter of the squeezed vacuum reservoir on the quantum entanglement and quantum discord. By numerical analysis,we conclude that the quantum entanglement and quantum discord will be reduced with the increases of the atomic initial state parameter and the squeeze parameter. However the quantum entanglement reduces quicker than the quantum discord. Finally,we find that the existence time of the quantum discord is longer than that of the quantum entanglement when the atomic initial state parameter and the squeeze parameter have the same value.
引文
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