Thermal atom–atom entanglement in a nonlinear cavity

Sevda Mirzaei

Eugene K. Bashkirov

Alireza Keshavarz, Mohammad Mehdi Golshan

In this work we investigate the thermal entanglement between two-level atoms and photons in a nonlinear cavity. We consider intensity-dependent couplings and calculate the negativity, as a measure of atom-photonentanglement. The cavity is assumed to be at a temperature T, so that all number of photons, and at the same time, both atomic states, with definite probabilities, are present. We then demonstrate a condition under which the intensity-dependent coupling leads to entanglement. It is also shown that, as in the case of linear Jaynes- Cummings model, the thermal states of atoms and photons are never separable.

Eugene K. Bashkirov, Yulia A. Nikiforova

The entanglement between two identical two-level atoms successively passing thermal cavity and interacting with one-mode thermal field through a degenerate two-photon process is investigated. It is shown that two atoms can be entangled through such nonlinear interaction.

Mohsen Abbasi

Mikhail M. Evseev, Eugene K. Bashkirov

In this paper, we investigate entanglement between two two-level atoms when they simultaneously interact with a single-mode thermal field of a lossless cavity with Kerr medium. We show that a slight Kerr nonlinearity might enhance the degree of entanglement between the atoms. More interestingly, both atoms would somehow get entangled even when both atoms are initially in the excited state.