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Dynamical decoherence in a cavity with a large number of two-level atoms

Marco Frasca
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Abstract

We consider a large number of two-level atoms interacting with the mode of a cavity in the rotating-wave approximation (Tavis-Cummings model). We apply the Holstein-Primakoff transformation to study the model in the limit of the number of two-level atoms, all in their ground state, becoming very large. The unitary evolution that we obtain in this approximation is applied to a macroscopic superposition state showing that, when the coherent states forming the superposition are enough distant, then the state collapses on a single coherent state describing a classical radiation mode. This appear as a true dynamical effect that could be observed in experiments with cavities.

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Marco Frasca. 2004-02-09. Dynamical decoherence in a cavity with a large number of two-level atoms. https://doi.org/10.1088/0953-4075/37/6/011

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