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Dynamical phase transition in the open Dicke model.

ABSTRACT: The Dicke model with a weak dissipation channel is realized by coupling a Bose-Einstein condensate to an optical cavity with ultranarrow bandwidth. We explore the dynamical critical properties of the Hepp-Lieb-Dicke phase transition by performing quenches across the phase boundary. We observe hysteresis in the transition between a homogeneous phase and a self-organized collective phase with an enclosed loop area showing power-law scaling with respect to the quench time, which suggests an interpretation within a general framework introduced by Kibble and Zurek. The observed hysteretic dynamics is well reproduced by numerically solving the mean-field equation derived from a generalized Dicke Hamiltonian. Our work promotes the understanding of nonequilibrium physics in open many-body systems with infinite range interactions.

SUBMITTER: Klinder J

PROVIDER: S-EPMC4371957 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Dynamical phase transition in the open Dicke model.

Klinder Jens J Keßler Hans H Wolke Matthias M Mathey Ludwig L Hemmerich Andreas A

Proceedings of the National Academy of Sciences of the United States of America 20150302 11

The Dicke model with a weak dissipation channel is realized by coupling a Bose-Einstein condensate to an optical cavity with ultranarrow bandwidth. We explore the dynamical critical properties of the Hepp-Lieb-Dicke phase transition by performing quenches across the phase boundary. We observe hysteresis in the transition between a homogeneous phase and a self-organized collective phase with an enclosed loop area showing power-law scaling with respect to the quench time, which suggests an interpr ...[more]

PMID: 25733892

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