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Critical Property of Geometric Phase in the Dicke Model

Gang Chen·Juqi Li·J. -Q. Liang
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Abstract

We obtain the ground-state energy level and associated geometric phase in the Dicke model analytically by means of the Holstein-Primakoff transformation and the boson expansion approach in the thermodynamic limit. The non-adiabatic geometric phase induced by the photon field is derived with the time-dependent unitary transformation. It is shown that the quantum phase transition characterized by the non-analyticity of the geometric phase is remarkably of the first-order. We also investigate the scaling behavior of the geometric phase at the critical point, which can be measured in a practical experiment to detect the quantum phase transition.

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Gang Chen, Juqi Li, J. -Q. Liang. 2006-08-28. Critical Property of Geometric Phase in the Dicke Model. https://doi.org/10.1103/physreva.74.054101

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