Acta Physica Sinica

Entanglement and intrinsic decoherence in the interaction between two-mode field and atom

Xia Tan, Zhang Cheng-qiang, Yun‐Jie Xia, 曲阜师范大学物理工程学院，曲阜 273165

Published Jan 1, 2006• 5 citations

Abstract

Considering the interaction between two-mode SU(1,1) coherence states and a two-level atom, we find an exact solution of the Milburn equation for the system. We investigate the time evolution of the entanglement of field-atom and one of two modes of field using the quantum-reduced entropy and quantum relative entropy, respectively. The influences of intrinsic decoherence and two-mode photon number difference on the evolution of the entanglement of field-atom and one of two modes of field are discussed. It is shown that the entanglement of field-atom reduces to a stationary value with time evolution and the entanglement between two modes increases to another stationary value with intrinsic decoherence, and the values only depend on the two-mode photon number and mean photon number.

DOI: 10.7498/aps.55.2263

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