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arXiv · 1503.03953

Large-N scaling behavior of the quantum fisher information in the Dicke model

Yu-Yu Zhang·Xiang-You Chen
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Abstract

Quantum Fisher information (QFI) of the reduced two-atom state is employed to capture the quantum criticality of the superradiant phase transition in the Dicke model in the infinite size and finite-$N$ systems respectively. The analytical expression of the QFI of its ground state is evaluated explicitly. And finite-size scaling analysis is performed with the large accessible system size due to the effective bosonic coherent-state technique. We also investigate the large-size scaling behavior of the scaled QFI of the reduced $N$-atom state and show the accurate exponent.

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Yu-Yu Zhang, Xiang-You Chen. 2015-10-08. Large-N scaling behavior of the quantum fisher information in the Dicke model. https://doi.org/10.1140/epjd%2Fe2015-60323-1

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