We have studied entanglement evolution and transfer in a double Tavis-Cumming model where two pairs of entangled two-level atoms AB and CD interact with two single-mode cavity fields a and b. We show that the Bellwlik...We have studied entanglement evolution and transfer in a double Tavis-Cumming model where two pairs of entangled two-level atoms AB and CD interact with two single-mode cavity fields a and b. We show that the Bellwlike initial state of atoms AB can exhibit entanglement sudden death which should be independent of the initial entanglement of atoms CD. Also, we show that the initial entanglement of one atomic pair can be transferred into another pair, as well as the possible subsystems, that become entangled during evolution.展开更多
This paper investigates the entanglement evolution of a two-qubit anisotropic Heisenberg XYZ chain in the presence of Dzyaloshinskii-Moriya interaction. The time evolution of the concurrence is studied for the initial...This paper investigates the entanglement evolution of a two-qubit anisotropic Heisenberg XYZ chain in the presence of Dzyaloshinskii-Moriya interaction. The time evolution of the concurrence is studied for the initial pure entangled states cosθ｜00〉 ＋ sinθ ｜11〉 and cos Ф ｜01〉 ＋ sin Ф10〉 at zero temperature. The influences of Dzyaloshinskii Moriya interaction D, anisotropic parameter △ and environment coupling strength γ on entanglement evolution are analysed in detail. It is found that the effect of noisy environment obviously suppresses the entanglement evolution, and the Dzyaloshinskii-Moriya interaction D acts on the time evolution of entanglement only when the initial state is cos Ф ｜01〉 sinФ｜10〉. Finally, a formula of steady state concurrence is obtained, and it is shown that the stable concurrence, which is independent of different initial states and Dzyaloshinskii-Moriya interaction D, depends on the anisotropic parameter △ and the environment coupling strength.展开更多
The explicit form of the evolution operator for the three-atom Tavis-Cummings model is given. The atoms can be entangled through their interaction with a thermal field. The degree of entanglement depends on the mean p...The explicit form of the evolution operator for the three-atom Tavis-Cummings model is given. The atoms can be entangled through their interaction with a thermal field. The degree of entanglement depends on the mean photon number of the thermal field and the initial state of the atoms.展开更多
We model of intrinsic analyze the time evolution of entanglement of two-qutrit system within the framework of Milburn＇s decoherence. The entanglement evolution relies not only on the parameters of system, but also on...We model of intrinsic analyze the time evolution of entanglement of two-qutrit system within the framework of Milburn＇s decoherence. The entanglement evolution relies not only on the parameters of system, but also on the concrete states either pure or mixed. The linear entropy used to measure the extent to which the intrinsic decoherenee affects quantum states is evaluated.展开更多
Considering two identical two-level atoms interacting with a single-model dissipative coherent cavity field without rotating wave approximation, we explore the entanglement dynamics of the two atoms prepared in differ...Considering two identical two-level atoms interacting with a single-model dissipative coherent cavity field without rotating wave approximation, we explore the entanglement dynamics of the two atoms prepared in different states using concurrence. Interestingly, our results show that the entanglement between the two atoms that initially disentangled will come up to a large constant rapidly, and then keeps steady in the following time or always has its maximum when prepared in some special Bell states. The model considered in this study is a good candidate for quantum information processing especially for quantum computation as steady high-degree atomic entanglement resource obtained in dissipative cavit.展开更多
文摘We have studied entanglement evolution and transfer in a double Tavis-Cumming model where two pairs of entangled two-level atoms AB and CD interact with two single-mode cavity fields a and b. We show that the Bellwlike initial state of atoms AB can exhibit entanglement sudden death which should be independent of the initial entanglement of atoms CD. Also, we show that the initial entanglement of one atomic pair can be transferred into another pair, as well as the possible subsystems, that become entangled during evolution.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10904033)Educational Commission of Hubei Province (Grant No. D20092204)Natural Science Foundation of Hubei Normal University (Grant No. 2007D21)
文摘This paper investigates the entanglement evolution of a two-qubit anisotropic Heisenberg XYZ chain in the presence of Dzyaloshinskii-Moriya interaction. The time evolution of the concurrence is studied for the initial pure entangled states cosθ｜00〉 ＋ sinθ ｜11〉 and cos Ф ｜01〉 ＋ sin Ф10〉 at zero temperature. The influences of Dzyaloshinskii Moriya interaction D, anisotropic parameter △ and environment coupling strength γ on entanglement evolution are analysed in detail. It is found that the effect of noisy environment obviously suppresses the entanglement evolution, and the Dzyaloshinskii-Moriya interaction D acts on the time evolution of entanglement only when the initial state is cos Ф ｜01〉 sinФ｜10〉. Finally, a formula of steady state concurrence is obtained, and it is shown that the stable concurrence, which is independent of different initial states and Dzyaloshinskii-Moriya interaction D, depends on the anisotropic parameter △ and the environment coupling strength.
文摘The explicit form of the evolution operator for the three-atom Tavis-Cummings model is given. The atoms can be entangled through their interaction with a thermal field. The degree of entanglement depends on the mean photon number of the thermal field and the initial state of the atoms.
基金the National Fundamental Research Program of China under Grant No.60573008
文摘We model of intrinsic analyze the time evolution of entanglement of two-qutrit system within the framework of Milburn＇s decoherence. The entanglement evolution relies not only on the parameters of system, but also on the concrete states either pure or mixed. The linear entropy used to measure the extent to which the intrinsic decoherenee affects quantum states is evaluated.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10374025)the Education Ministry of Hunan Province,China (Grant No. 06A038)the Natural Science Foundation of Hunan Province,China (Grant No. 07JJ3013
文摘Considering two identical two-level atoms interacting with a single-model dissipative coherent cavity field without rotating wave approximation, we explore the entanglement dynamics of the two atoms prepared in different states using concurrence. Interestingly, our results show that the entanglement between the two atoms that initially disentangled will come up to a large constant rapidly, and then keeps steady in the following time or always has its maximum when prepared in some special Bell states. The model considered in this study is a good candidate for quantum information processing especially for quantum computation as steady high-degree atomic entanglement resource obtained in dissipative cavit.
