arXiv:quant-ph/0603191 · Physical Review A
Entanglement and decoherence of N atoms and a mesoscopic field in a cavity
Tristan Meunier, Arnaud Le Diffon, Clément Ruef, Pascal Degiovanni, J. M. Raimond
Abstract
We investigate the behavior of $N$ atoms resonantly coupled to a single electromagnetic field mode sustained by a high quality cavity, containing a mesoscopic coherent field. We show with a simple effective Hamiltonian model that the strong coupling between the cavity and the atoms produces an atom-field entangled state, involving $N+1$ nearly coherent components slowly rotating at different paces in the phase plane. The periodic overlap of these components results in a complex collapse and revival pattern for the Rabi oscillation. We study the influence of decoherence due to the finite cavity quality factor. We propose a simple analytical model, based on the Monte Carlo approach to relaxation. We compare its predictions with exact calculations and show that these interesting effects could realistically be observed on a two or three atoms sample in a 15 photon field with circular Rydberg atoms and superconducting cavities.