Coherence loss of large fields interacting with two-level atoms

Jian-Song Zhang, PING YU, Aixi Chen

We investigate the entanglement dynamics and coherence loss of a two-level atom dispersively interacting with two coherent fields in a dissipative cavity by using the concurrence and linear entropy, respectively. It is shown that the atomic coherence can lead to entanglement between the atom and one mode while the two modes are always separable. We also find that there is long-lived coherence loss as the system evolves.

Zhiming Huang

Masashi Ban

Decoherence of the dispersive Jaynes–Cummings model which is placed in a lossy cavity is studied by means of the time-convolutionless non-Markovian quantum master equation. The effect of the interaction between a two-level atom and photon field on the damping operator of the quantum master equation is made clear by calculating the decay of coherence and entanglement of the relevant system. It is shown that although the interaction effect on the damping operator is small when the cavity loss has the Markovian property, it becomes significantly large when the cavity loss is subject to the non-Markovian process. Furthermore, the quantum channel of the two-level atom derived by the dispersive Jaynes–Cummings model is investigated. The decay of entanglement of the two two-level atoms is examined to show the importance of the interaction effect on the damping operator.

Jun-Xiang, Zhang, Yabin +5 more

Qing-Xia Mu, Yonghong Ma, Ling Zhou

A scheme is presented for the generation of entangled coherent states in a single-atom cavity-QED system. In the scheme, a three-level V -type atom interacts dispersively with a two-mode cavity and is driven by a classical field. We show that under large detuning conditions the cavity field can evolve into maximally entangled coherent states when one cavity mode is initially prepared in an odd coherent state. The effect of the cavity losses on the entanglement is also studied.