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arXiv · 1206.5131

Finite-size scaling in the quantum phase transition of the open-system Dicke-model

G. Konya·D. Nagy·G. Szirmai·P. Domokos
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Abstract

Laser-driven Bose-Einstein condensate of ultracold atoms loaded into a lossy high-finesse optical resonator exhibits critical behavior and, in the thermodynamic limit, a phase transition between stationary states of different symmetries. The system realizes an open-system variant of the celebrated Dicke-model. We study the transition for a finite number of atoms by means of a Hartree-Fock-Bogoliubov method adapted to a damped-driven open system. The finite-size scaling exponents are determined and a clear distinction between the non-equilibrium and the equilibrium quantum criticality is found.

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G. Konya, D. Nagy, G. Szirmai, P. Domokos. 2012-06-22. Finite-size scaling in the quantum phase transition of the open-system Dicke-model. https://doi.org/10.1103/physreva.86.013641

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