In this paper, the entanglement dynamics of a double two-photon Jaynes-Cummings model with Kerr-like medium is investigated. It is shown that initial entanglement has an interesting subsequent time evolution, includin...In this paper, the entanglement dynamics of a double two-photon Jaynes-Cummings model with Kerr-like medium is investigated. It is shown that initial entanglement has an interesting subsequent time evolution, including the so-called entanglement sudden death effect. It is also shown analytically that the Kerr-like medium can repress entanglement sudden death and enhance the degree of atom-atom entanglement. A more interesting fact is that the Kerr effect is more obvious when each of the two cavities with have the Kerr-like medium than only one of them with the Kerr-like medium.展开更多
The entanglement dynamics of system, where atoms A and B interact with single mode cavity fields a and b respectively, is studied. The interaction between atom A and cavity a may be described by using the typical Jayn...The entanglement dynamics of system, where atoms A and B interact with single mode cavity fields a and b respectively, is studied. The interaction between atom A and cavity a may be described by using the typical Jaynes Cummings model, while that between the atom B and cavity b filled with a Kerr medium is of a two-photon process. For a certain initial atom entanglement state, there is an entanglement sudden death effect between the two atoms. The Kerr medium in the cavity b can effectively prevent the undesirable entanglement sudden death from occurring. Also, from the viewpoint of the population dynamics, we discuss why the Kerr medium can do so.展开更多
We study entanglement dynamics of three-qubit system via negativity. Three atoms A, B, and C interact isolatedly with their own Jaynes-Cummings cavities a, b, and c. Aa system is prepared entangled with Bb and Cc, how...We study entanglement dynamics of three-qubit system via negativity. Three atoms A, B, and C interact isolatedly with their own Jaynes-Cummings cavities a, b, and c. Aa system is prepared entangled with Bb and Cc, however, their mutual isolations forbid Aa interacting with system Bb and Cc. It is the same for system Bb and Cc. We show entanglement evolution of different three-qubit systems ABC, abc, Abc, and aBC and find entanglement sudden death effect.展开更多
We study the entanglement dynamics for a double Jaynes-Cummings model where two entangled atoms A and B locally interact with independent cavities a and b, respectively, but there are no interactions between locations...We study the entanglement dynamics for a double Jaynes-Cummings model where two entangled atoms A and B locally interact with independent cavities a and b, respectively, but there are no interactions between locations Aa and Bb. We point out that there exists a parameter range in which simultaneous pairwise entanglement sudden death (ESD) for remote parties, i.e. AB, ab, Ab and Ba, may occur. We show that during this simultaneous ESD period various multipartite entanglement can be created. Our results imply that the pairwise entanglement between two independent locations may be transferred into other multipartite forms which account for the correlations between the two independent locations.展开更多
We investigate the properties of entanglement between an isolated atom and a Jaynes-Cummings atom in the presence of transient effects. These effects are due to the modulation of the atom-field coupling whose explicit...We investigate the properties of entanglement between an isolated atom and a Jaynes-Cummings atom in the presence of transient effects. These effects are due to the modulation of the atom-field coupling whose explicit time-dependence is considered for the case of the linear sweep. We show that the sudden death of entanglement can be controlled by the transient effects. These effects can suppress the sudden death of entanglement in time.展开更多
Extending the double Jaynes Cummings model to a more complicated case where the mode-mode competition is considered, we investigate the entanglement character of two isolated atoms by means of concurrence, and discuss...Extending the double Jaynes Cummings model to a more complicated case where the mode-mode competition is considered, we investigate the entanglement character of two isolated atoms by means of concurrence, and discuss the dependence of atom atom entanglement on the different initial state and the relative coupling strength between the atom and the corresponding cavity field. The results show that the amplitude and the period of the atom atom entanglement evolution can be controlled by the choice of initial state and relative coupling strength, respectively. We find that the phenomenon of entanglement sudden death （ESD） is sensitive to the initial conditions. The length of the time interval for zero entanglement depends not only on the initial degree of entanglement between two atoms but also on the relative coupling strength of atom field interaction. The ESD effect can be weakened by enhancing the mode-mode competition between the three- and single-photon processes.展开更多
We investigate the evolution of initial entangled two-atom in cavity with single-mode light field. Using the method of negative eigenvalue of partially transposed matrix we analysis the evolution of the entanglement o...We investigate the evolution of initial entangled two-atom in cavity with single-mode light field. Using the method of negative eigenvalue of partially transposed matrix we analysis the evolution of the entanglement of the two-atom in a field of number state and Kerr-media environment and find that entanglement sudden death phenomenon occurs in the number of particles field. When the atoms interact with the Kerr medium, we obtain that the phenomenon of sudden death can be eliminated in the particle-number field, and the entanglement of two-atom oscillates around a high-value.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No. 10374025)the Natural Science Foundation of Hunan Province of China (Grant No. 07JJ3013)the Education Ministry of Hunan Province of China (Grant No. 06A038)
文摘In this paper, the entanglement dynamics of a double two-photon Jaynes-Cummings model with Kerr-like medium is investigated. It is shown that initial entanglement has an interesting subsequent time evolution, including the so-called entanglement sudden death effect. It is also shown analytically that the Kerr-like medium can repress entanglement sudden death and enhance the degree of atom-atom entanglement. A more interesting fact is that the Kerr effect is more obvious when each of the two cavities with have the Kerr-like medium than only one of them with the Kerr-like medium.
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10535010 and 10775123)the Research Foundation from Ministry of Education of China (contract No 20070284016)
文摘The entanglement dynamics of system, where atoms A and B interact with single mode cavity fields a and b respectively, is studied. The interaction between atom A and cavity a may be described by using the typical Jaynes Cummings model, while that between the atom B and cavity b filled with a Kerr medium is of a two-photon process. For a certain initial atom entanglement state, there is an entanglement sudden death effect between the two atoms. The Kerr medium in the cavity b can effectively prevent the undesirable entanglement sudden death from occurring. Also, from the viewpoint of the population dynamics, we discuss why the Kerr medium can do so.
文摘We study entanglement dynamics of three-qubit system via negativity. Three atoms A, B, and C interact isolatedly with their own Jaynes-Cummings cavities a, b, and c. Aa system is prepared entangled with Bb and Cc, however, their mutual isolations forbid Aa interacting with system Bb and Cc. It is the same for system Bb and Cc. We show entanglement evolution of different three-qubit systems ABC, abc, Abc, and aBC and find entanglement sudden death effect.
基金supported by the National Natural Science Foundation of China (10774088).
文摘We study the entanglement dynamics for a double Jaynes-Cummings model where two entangled atoms A and B locally interact with independent cavities a and b, respectively, but there are no interactions between locations Aa and Bb. We point out that there exists a parameter range in which simultaneous pairwise entanglement sudden death (ESD) for remote parties, i.e. AB, ab, Ab and Ba, may occur. We show that during this simultaneous ESD period various multipartite entanglement can be created. Our results imply that the pairwise entanglement between two independent locations may be transferred into other multipartite forms which account for the correlations between the two independent locations.
文摘We investigate the properties of entanglement between an isolated atom and a Jaynes-Cummings atom in the presence of transient effects. These effects are due to the modulation of the atom-field coupling whose explicit time-dependence is considered for the case of the linear sweep. We show that the sudden death of entanglement can be controlled by the transient effects. These effects can suppress the sudden death of entanglement in time.
基金Project supported by the National Natural Science Foundation of China (Grant No 10374025)the Foundation of Education Department of Hunan Province of China (Grant Nos 06A038 and 06C080)the Science and Technology Project of Zhanjiang City (Grant No 2008C10019)
文摘Extending the double Jaynes Cummings model to a more complicated case where the mode-mode competition is considered, we investigate the entanglement character of two isolated atoms by means of concurrence, and discuss the dependence of atom atom entanglement on the different initial state and the relative coupling strength between the atom and the corresponding cavity field. The results show that the amplitude and the period of the atom atom entanglement evolution can be controlled by the choice of initial state and relative coupling strength, respectively. We find that the phenomenon of entanglement sudden death （ESD） is sensitive to the initial conditions. The length of the time interval for zero entanglement depends not only on the initial degree of entanglement between two atoms but also on the relative coupling strength of atom field interaction. The ESD effect can be weakened by enhancing the mode-mode competition between the three- and single-photon processes.
文摘We investigate the evolution of initial entangled two-atom in cavity with single-mode light field. Using the method of negative eigenvalue of partially transposed matrix we analysis the evolution of the entanglement of the two-atom in a field of number state and Kerr-media environment and find that entanglement sudden death phenomenon occurs in the number of particles field. When the atoms interact with the Kerr medium, we obtain that the phenomenon of sudden death can be eliminated in the particle-number field, and the entanglement of two-atom oscillates around a high-value.
