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arXiv · 1004.5041

Circuit QED scheme for realization of the Lipkin-Meshkov-Glick model

Jonas Larson
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Abstract

We propose a scheme in which the Lipkin-Meshkov-Glick model is realized within a circuit QED system. An array of N superconducting qubits interacts with a driven cavity mode. In the dispersive regime, the cavity mode is adiabatically eliminated generating an effective model for the qubits alone. The characteristic long-range order of the Lipkin-Meshkov-Glick model is here mediated by the cavity field. For a closed qubit system, the inherent second order phase transition of the qubits is reflected in the intensity of the output cavity field. In the broken symmetry phase, the many-body ground state is highly entangled. Relaxation of the qubits is analyzed within a mean-field treatment. The second order phase transition is lost, while new bistable regimes occur.

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Jonas Larson. 2010-06-17. Circuit QED scheme for realization of the Lipkin-Meshkov-Glick model. https://doi.org/10.1209/0295-5075%2F90%2F54001

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