Journal of Optoelectronics·laser

The Entanglement Evolution of Two Λ-type Three-level Atoms in a Two-mode Cavity Field

Yun‐Jie Xia

Published Jan 1, 2007• 0 citations

Abstract

We investigate the Raman coupled model of two entangled Λ-type three-level atoms interacting with a two-mode quantized cavity field.With the negative eignevalues of the partial transposition matrix,we obtain the time evolution of entanglement between the two atoms.The results show that the entanglement of the two atoms displays periodicity;the evolution regular of entanglement is influenced by the initial state of two atoms and initial photon number of the cavity.For special initial state,the two-atom quantum state will stay in the maximum entangled state forever and have no relation with the initial photon number.Compared with Tavis-Commings model,the entanglement of the two atoms can live for much longer time in the proposed model.

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