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Entanglement and decoherence of N atoms and a mesoscopic field in a cavity

Tristan Meunier·Arnaud Le Diffon·Clément Rueff·Pascal Degiovanni·Jean-Michel Raimond
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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 photons field with circular Rydberg atoms and superconducting cavities.

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Tristan Meunier, Arnaud Le Diffon, Clément Rueff, Pascal Degiovanni, Jean-Michel Raimond. 2006-03-22. Entanglement and decoherence of N atoms and a mesoscopic field in a cavity. https://doi.org/10.1103/physreva.74.033802

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