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arXiv · 0909.1725

Entangled States and Super-radiant Phase Transition

M. Aparicio Alcalde·A. H. Cardenas·N. F. Svaiter·V. B. Bezerra
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Abstract

The Dicke spin-boson model is composed by a single bosonic mode and an ensemble of $N$ identical two-level atoms. Assuming thermal equilibrium with a reservoir at temperature $β^{-1}$, we consider the situation where the coupling between the bosonic mode and the atoms generates resonant and non-resonant processes. The thermodynamic of the model is investigated. Next we introduce dipole-dipole interaction between the atoms. We investigate the transition from fluorescent to super-radiant phase and the quantum phase transition in a situation where the dipole-dipole interaction between the atoms generates entangled states in the atomic system. We proved that, the critical behavior is not modified by the introduction of the dipole-dipole interaction.

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M. Aparicio Alcalde, A. H. Cardenas, N. F. Svaiter, V. B. Bezerra. 2009-09-09. Entangled States and Super-radiant Phase Transition. https://doi.org/10.1103/physreva.81.032335

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