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Entanglement and the Phase Transition in Single Mode Superradiance

Neill Lambert·Clive Emary·Tobias Brandes
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Abstract

We consider the entanglement properties of the quantum phase transition in the single-mode superradiance model, involving the interaction of a boson mode and an ensemble of atoms. For infinite system size, the atom-field entanglement of formation diverges logarithmically with the correlation length exponent. Using a continuous variable representation, we compare this to the divergence of the entropy in conformal field theories, and derive an exact expression for the scaled concurrence and the cusp-like non-analyticity of the momentum squeezing.

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Neill Lambert, Clive Emary, Tobias Brandes. 2003-09-02. Entanglement and the Phase Transition in Single Mode Superradiance. https://doi.org/10.1103/physrevlett.92.073602

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