arXiv:quant-ph/0507025

Entanglement, chaos and atomic Wigner function of the Dicke model

L. Sanz, K. Furuya

Published Jul 4, 2005• 0 citations

Abstract

We calculate the atomic (spin) Wigner function for the single mode Dicke model in the regime of large number of two-level atoms. The dynamics of this quasi-probability function on the Bloch sphere allows us to visualize the consequences of the entanglement process between the boson and the spin subsystems. Such investigation shows a distinct localization behavior of the spin state with respect to the polar and azimuthal Bloch sphere angles. A complete {\em breakdown of reflection symmetry} in the azimuthal angle is shown in the non-integrable case, even at short evolution times. Also, in the classically chaotic situation, the appearance of {\em sub-planck structures} in the Wigner function is shown, and its evolution analyzed.

DOI: 10.48550/arxiv.quant-ph/0507025

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