Influence of phase decoherence on entanglement of two atoms in multiphoton process

Abstract

Abstract:

By means of the quantum theory and negative eigenvalues of the partial transposition, the properties of entanglement evolution in the system of two two-level atoms coupled to a light field in the Fock state are investigated in the presence of phase decoherence in the multiphoton Tavis-Cumming Model. The influences of the phase decoherence coefficient, the dipole-dipole coupling intensity and the number of the transitional photons on the properties of the entanglement evolution between two atoms have been discussed. The results show that the phase decoherence doesn’t destroy coherence completely but attenuates oscillated amplitude of the entanglement degree between two entangled atoms, then the entanglement degree will quickly become a constant. With the increasing of the phase decoherence coefficient and the number of the transitional photons, the time for the two entangled atoms that approach the state in which there is a stable entanglement degree will be shortened gradually. The bigger the dipole interaction between two atoms，the better the coherences between two atoms. Thus the larger value of entanglement degree between two entangled atoms could be obtained and the state in which two entangled atoms are is more stable in a relatively short time.

Key words: quantum optics, entangled characteristic, negative eigenvalues of partial transposition, phase decoherence

CLC Number:

O431.2

ZHANG Dongxia, Sachuerfu, Muqier. Influence of phase decoherence on entanglement of two atoms in multiphoton process[J]. J4, 2011, 28(4): 439-445.

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