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arXiv · 0802.3972

Exotic quantum phase transitions in a Bose-Einstein condensate coupled to an optical cavity

Gang Chen·Xiaoguang Wang·J. -Q. Liang·Z. D. Wang
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Abstract

A new extended Dicke model, which includes atom-atom interactions and a driving classical laser field, is established for a Bose-Einstein condensate inside an ultrahigh-finesse optical cavity. A feasible experimental setup with a strong atom-field coupling is proposed, where most parameters are easily controllable and thus the predicted second-order superradiant-normal phase transition may be detected by measuring the ground-state atomic population. More intriguingly, a novel second-order phase transition from the superradiant phase to the \textquotedblleft Mott" phase is also revealed. In addition, a rich and exotic phase diagram is presented.

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Gang Chen, Xiaoguang Wang, J. -Q. Liang, Z. D. Wang. 2008-03-17. Exotic quantum phase transitions in a Bose-Einstein condensate coupled to an optical cavity. https://doi.org/10.1103/physreva.78.023634

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