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arXiv · 1101.3760

Multimode mean-field model for the quantum phase transition of a Bose-Einstein condensate in an optical resonator

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

We develop a mean-field model describing the Hamiltonian interaction of ultracold atoms and the optical field in a cavity. The Bose-Einstein condensate is properly defined by means of a grand-canonical approach. The model is efficient because only the relevant excitation modes are taken into account. However, the model goes beyond the two-mode subspace necessary to describe the self-organization quantum phase transition observed recently. We calculate all the second-order correlations of the coupled atom field and radiation field hybrid bosonic system, including the entanglement between the two types of fields.

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G. Konya, G. Szirmai, P. Domokos. 2011-01-19. Multimode mean-field model for the quantum phase transition of a Bose-Einstein condensate in an optical resonator. https://doi.org/10.1140/epjd%2Fe2011-20050-3

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