Considering the dipole-dipole coupling intensity between two atoms and the field in the Fock state, the entanglement dynamics between two atoms that are initially entangled in the system of two two-level atoms coupled...Considering the dipole-dipole coupling intensity between two atoms and the field in the Fock state, the entanglement dynamics between two atoms that are initially entangled in the system of two two-level atoms coupled to a single mode cavity in the presence of phase decoherence has been investigated. The two-atom entanglement appears with periodicity without considering phase decoherence, however, the phase decoherence causes the decay of entanglement between two atoms, with the increasing of the phase decoherence coefficient, the entanglement will quickly become a constant value, which is affected by the two-atom initial state. Meanwhile the two-atom quantum state will forever stay in the maximal entangled state when the initial state is proper even in the presence of phase decoherence. On the other hand, the Bell violation and the entanglement do not satisfy the monotonous relation, a large Bell violation implies the presence of a large amount of entanglement under certain conditions, while a large Bell violation corresponds to a little amount of entanglement in certain situations. However, the violation of Bell-CHSH inequality can reach the maximal value if two atoms are in the maximal entangled state, or vice versa.展开更多
The relations between Wehrl’s entropy and squeezing or total noise in the field with Gaussian Q function are established,The results show that,the Wehrl’s entropy will be reduced when the squeezing is increased or t...The relations between Wehrl’s entropy and squeezing or total noise in the field with Gaussian Q function are established,The results show that,the Wehrl’s entropy will be reduced when the squeezing is increased or the total noise is decreased.The other nonclassical properties in this kind of field are also discussed.展开更多
For Fe layers covered by two-dimensional arrays of hexagonal close-packed polystyrene spheres which are hemispherically covered by Au films on the top,fine structures are observed in reflection,magneto-optical Kerr ro...For Fe layers covered by two-dimensional arrays of hexagonal close-packed polystyrene spheres which are hemispherically covered by Au films on the top,fine structures are observed in reflection,magneto-optical Kerr rotation and ellipticity spectra.The Kerr rotation achieves peaks or exhibits a narrow resonance-like spectral lineshape near the reflection minima,depending on the mechanism of the reflection dips.The Kerr rotation peaks and the resonance-like lineshape both are shifted with the sphere diameters.These phenomena can be attributed to the excitation of surface plasmon resonance and Fabry–Pérot modes.展开更多
In the context of cavity quantum electrodynamics (QED),a potential scheme is proposed to generate entangled coherent states. The scheme includes twice interactions of two-level atoms with cavities. In the first intera...In the context of cavity quantum electrodynamics (QED),a potential scheme is proposed to generate entangled coherent states. The scheme includes twice interactions of two-level atoms with cavities. In the first interaction,two atoms are sent into a microwave cavity with the large detuning respectively. And then the second interaction is that the two atoms enter another microwave cavity and are driven by a resonant classical field meantime. When we choose the proper interaction time and make measurement on the two atoms,the two microwave cavity mode fields are determinatively entangled. In addition,it is easy to generalize the scheme to multi-cavity and multi-atom.展开更多
基金the Key Program of National Natural Science Foundation of China under Grant No.10534030Key Higher Education Program of Hubei Province under Grant No.Z20052201+1 种基金the Natural Science Foundation of Hubei Province under Grant No.2006ABA055the Postgraduate Program of Hubei Normal University under Grant No.2007D20
文摘Considering the dipole-dipole coupling intensity between two atoms and the field in the Fock state, the entanglement dynamics between two atoms that are initially entangled in the system of two two-level atoms coupled to a single mode cavity in the presence of phase decoherence has been investigated. The two-atom entanglement appears with periodicity without considering phase decoherence, however, the phase decoherence causes the decay of entanglement between two atoms, with the increasing of the phase decoherence coefficient, the entanglement will quickly become a constant value, which is affected by the two-atom initial state. Meanwhile the two-atom quantum state will forever stay in the maximal entangled state when the initial state is proper even in the presence of phase decoherence. On the other hand, the Bell violation and the entanglement do not satisfy the monotonous relation, a large Bell violation implies the presence of a large amount of entanglement under certain conditions, while a large Bell violation corresponds to a little amount of entanglement in certain situations. However, the violation of Bell-CHSH inequality can reach the maximal value if two atoms are in the maximal entangled state, or vice versa.
文摘The relations between Wehrl’s entropy and squeezing or total noise in the field with Gaussian Q function are established,The results show that,the Wehrl’s entropy will be reduced when the squeezing is increased or the total noise is decreased.The other nonclassical properties in this kind of field are also discussed.
基金Supported by the National Natural Science Foundation of China under Grant Nos 51171129,10974032the National Basic Research Program of China under Grant No 2009CB929201Shanghai Committee of Science and Technology under Grant No 11JC1412700。
文摘For Fe layers covered by two-dimensional arrays of hexagonal close-packed polystyrene spheres which are hemispherically covered by Au films on the top,fine structures are observed in reflection,magneto-optical Kerr rotation and ellipticity spectra.The Kerr rotation achieves peaks or exhibits a narrow resonance-like spectral lineshape near the reflection minima,depending on the mechanism of the reflection dips.The Kerr rotation peaks and the resonance-like lineshape both are shifted with the sphere diameters.These phenomena can be attributed to the excitation of surface plasmon resonance and Fabry–Pérot modes.
基金the National Science Foundation of China (Grant No.10774088)the Key Program of National Science Foundation of China (Grant No.10534030)Funds from Qufu Normal University (Grant No.XJ0621)
文摘In the context of cavity quantum electrodynamics (QED),a potential scheme is proposed to generate entangled coherent states. The scheme includes twice interactions of two-level atoms with cavities. In the first interaction,two atoms are sent into a microwave cavity with the large detuning respectively. And then the second interaction is that the two atoms enter another microwave cavity and are driven by a resonant classical field meantime. When we choose the proper interaction time and make measurement on the two atoms,the two microwave cavity mode fields are determinatively entangled. In addition,it is easy to generalize the scheme to multi-cavity and multi-atom.
