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arXiv · 1411.5199

The Dicke model as the contraction limit of a pseudo-deformed Richardson-Gaudin model

Pieter W. Claeys·Stijn De Baerdemacker·Mario Van Raemdonck·Dimitri Van Neck
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Abstract

The Dicke model is derived in the contraction limit of a pseudo-deformation of the quasispin algebra in the su(2)-based Richardson-Gaudin models. Likewise, the integrability of the Dicke model is established by constructing the full set of conserved charges, the form of the Bethe Ansatz state, and the associated Richardson-Gaudin equations. Thanks to the formulation in terms of the pseudo-deformation, the connection from the su(2)-based Richardson-Gaudin model towards the Dicke model can be performed adiabatically.

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Pieter W. Claeys, Stijn De Baerdemacker, Mario Van Raemdonck, Dimitri Van Neck. 2014-11-19. The Dicke model as the contraction limit of a pseudo-deformed Richardson-Gaudin model. https://doi.org/10.1088/1742-6596/597/1/012025

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