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Ground-State Fidelity and Bipartite Entanglement in the Bose-Hubbard Model

Pierfrancesco Buonsante·Alessandro Vezzani
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Abstract

We analyze the quantum phase transition in the Bose-Hubbard model borrowing two tools from quantum-information theory, i.e. the ground-state fidelity and entanglement measures. We consider systems at unitary filling comprising up to 50 sites and show for the first time that a finite-size scaling analysis of these quantities provides excellent estimates for the quantum critical point.We conclude that fidelity is particularly suited for revealing a quantum phase transition and pinning down the critical point thereof, while the success of entanglement measures depends on the mechanisms governing the transition.

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Pierfrancesco Buonsante, Alessandro Vezzani. 2007-03-17. Ground-State Fidelity and Bipartite Entanglement in the Bose-Hubbard Model. https://doi.org/10.1103/physrevlett.98.110601

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