Effect of linear modulation of the atom-field couplings on atom entanglement

Abstract

Abstract: Considering a model containing two two-level atoms and a single-mode cavity, we have studied the effects of the time-dependent atom-field couplings on entanglement between the two atoms when the two atoms are initially in an entangled state. The results show that, the time of initial entanglement preservation is very sensitive to the linear modulation of the atom-field couplings. Compared to the case of the constant coupling model, when the atom-field couplings change smoothly, the disappearance of the initial entanglement is delayed due to the linear modulation. However, the disappearance of the initial entanglement can be hastened for the sudden jump in the coupling.

Key words: quantum optics, quantum entanglement, atom-field coupling, linear modulation

CLC Number:

O431.2

HAN Yun-Xia, HU Yao-Hua. Effect of linear modulation of the atom-field couplings on atom entanglement[J]. J4, 2014, 31(6): 715-719.

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