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arXiv · 1105.0426

Exploring Symmetry Breaking at the Dicke Quantum Phase Transition

K. Baumann·R. Mottl·F. Brennecke·T. Esslinger
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Abstract

We study symmetry breaking at the Dicke quantum phase transition by coupling a motional degree of freedom of a Bose-Einstein condensate to the field of an optical cavity. Using an optical heterodyne detection scheme we observe symmetry breaking in real-time and distinguish the two superradiant phases. We explore the process of symmetry breaking in the presence of a small symmetry-breaking field, and study its dependence on the rate at which the critical point is crossed. Coherent switching between the two ordered phases is demonstrated.

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K. Baumann, R. Mottl, F. Brennecke, T. Esslinger. 2011-05-02. Exploring Symmetry Breaking at the Dicke Quantum Phase Transition. https://doi.org/10.1103/physrevlett.107.140402

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