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Quantum phase transition in the multi-mode Dicke model

Denis Tolkunov·Dmitry Solenov
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Abstract

An investigation of the quantum phase transition in both discrete and continuum field Dicke models is presented. A series of anticrossing features following the criticality is revealed in the band of the field modes. Critical exponents are calculated. We investigate the properties of a pairwise entanglement measured by a concurrence and obtain analytical results in the thermodynamic limit.

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Denis Tolkunov, Dmitry Solenov. 2006-11-30. Quantum phase transition in the multi-mode Dicke model. https://doi.org/10.1103/physrevb.75.024402

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